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BERGEY'S MANUAL 

OF 

DETERMINATIVE 
BACTERIOLOGY 



BERGEY'S MANUAL 

DETERMINATIVE 
BACTERIOLOGY 



BY 
ROBERT S. BREED 

Ixite Professor Emerilus, Cnrnell Universily, Geneva, New York 

E. G. D. MURRAY 

Research Professor, University of Western Ontario, 
London, Ontario, Canada 

NATHAN R. SMITH 

Senior Bacteriologist, Retired, Plant Industry Station, 
U. S. Department of Agriculture, Beltsville, Maryland 

and 

Ninety-four Contributors 

Whose Names Appear on the Immediately Following Pages 



SEVENTH EDITION 






BALTIMORE 

THE WILLIAMS & WILKINS COMPANY 

1957 



First Edition, August, 1923 

Second Edition, December, 1925 

Third Edition, January, 1930 

Fourth Edition, March, 1934 

Preprint of pages ix + 79 of Fifth Edition, October, 1938 

Fifth Edition, April, 1939 

Sixth Edition, January, 1948 

Seventh Edition, October, 1957 



COPYRIGHT ©, 1957 
The Williams & Wilkins Company 



Made in United States of America 



Library of Congress 

Catalog Card Number 

57-11183 



COMPOSED AND PRINTED AT THE 

WAVERLY PRESS, INC. 

Mt. Royal and Guilford Aves. 

Baltimore 2, Md., U. S. A. 



LIST OF CONTRIBUTORS 

Allen, 0. N., Mr. & Mrs. Rhizobium 285 

Andrewes, C. H. Virales 985 

Barker, H. Albert Methanococcus 473 

Butyrihacterium 577 

Zymobacterium 577 

Beger, H. Caulobacteraceae 212 

Siderocapsaceae 217 

Chlamydobacteriales 262 

Bier, Otto Calymmatobacterium 418 

Borman, E. K. Paracolobactrum 346 

Branham, Sara E. Neisseria 480 

Breed, R. S.f Introduction 1 

Considerations influencing the classification 4 

Methanomonadaceae 74 

Thiobaderiaceae 78 

Pholobacterium 193 

Protaminobacter 200 

Mycoplana 204 

Caulobacteraceae 212 

Siderocapsaceae 217 

Vibrio 229 

Methanobacterium 250 

Cellvibrio 250 

Cellfalcicula 252 

Spirillum 253 

Chlamydobacteriales 262 

Chromobacterium 292 

Alcaligenes 297 

Achromobacter 300 

Flavobacterium 309 

Agarbacterium 322 

Enter obacteriaceae 332 

Escherichia 335 

Aerobacter 341 

Klebsiella 344 

Serratia 359 

Pasteurella 395 

Bacteroidaceae 423 

Sphaerophorus 441 

Micrococcaceae 454 

Micrococcus 455 

Sarcina 467 

Brevibacteriaceae 490 

Cory neb acteriaceae 578 

Caryophanales 830 

Virales 985 

Numerous contributions to various other taxa 

Broom, J. C. Leptospira 907 

t Deceased. 

V 



VI 

Buchanan, R. E. 

Burkholder, Walter H. 



Campbell, L. Leon, Jr. 
Clark, F. A. 
Clise, Eleanore H. 



Conn, H. J. 

Couch, John N. 

Davis, Gordon E. 
Delwiche, Eugene A. 
Doetsch, R. N. 
Douglas, H. C. 

Dumas, Julien 
Elazari-Volcani, Benjamin 
Eltinge, Ethel 
Evans, James B. 
Freundt, E. A. 

Gordon, Ruth 

Hanks, John H. 
Hansen, Paul Arne 
Haupt, Herbert 
Haynes, William C. 
Kitchens, A. Parkerf 
Hofer, A. W. 

Hoffman, Heiner 

Holmes, Francis O. 
Honigberg, B. M. 
Hucker, George J. 



Huddleson, I. F. 
Janke, Alexander 



LIST OF CONTRIBUTORS 

How Bacteria are Named and Identified 15 

Paraspirilluni 257 

Beggiatoales 837 

Beggiatoaceae 837 

Leucotrichaceae 850 

Pseudomonas 89 

Xanthomonas 152 

Agrobacterium 288 

Erwinia 349 

Corynebacterium 579 

Beneckea 328 

Cellulomonas 601 

Pasteurella 395 

Eubacterium 552 

Catenabacterium 560 

Ramibacterium 563 

Cillobacterium 566 

Agrobacterium 288 

Alcaligenes 297 

Actinomycetales 694 

Actinoplanaceae 825 

Spirochaetales 892 

Propionibacteriaceae 569 

Microbacterium 600 

Hyphomicrobiales 276 

Peptococcus 474 

Shigella 384 

Halubacterium 207 

Chromobaclerium 292 

Staphylococcus 464 

Streptobacillus 451 

Mycoplasmatales 914 

Bacillus 613 

Mycobacterium 695 

Mycobacterium 695 

Erysipelothrix 599 

Actinobacillus 414 

Pseudomonas 89 

Dialister 440 

Azotomonas 198 

Azotobacteraceae 283 

Fusobacterium 436 

Sphaerophorus 441 

Virales 985 

Parasites of protozoa 927 

Micrococcus 455 

Gaffkya 466 

Leuconostoc 531 

Brucella 404 

Thiobacteriaceae 78 

Thiobacterium 79 



t Deceased. 



LIST OF CONTRIBUTORS 



Kalz, Gertrude G. 
Kelly, CD. 

Kirby, Harold, Jr. 
Kluyver, A. J.f 
Langford, G. C. 
Leathen, Wm. W. 
Lessel, Erwin F., Jr. 



Lochhead, A. G. 
McClung, L. S. 
McCoy, Elizabeth 
Merchant, I. A. 
Morse, E. V. 

Murray, E. G. D. 



Neitz, W, O. 
Nellis, Lois 
Niven, C. F. 

0rskov, J. 
Parker, CD. 
Pederson, Carl S. 



Pelczar, M. J. 

Peshkoff, M. A. 
Philip, Cornelius B. 



Pittman, Margaret 
Pringsheim, E. G. 



Macromonas 80 

Thiovulum 81 

Thiospira 82 

Salmonella 368 

Noguchia 421 

Bacteroides 424 

Parasites of protozoa 927 

Zymomonas 199 

Erysipelothrix 599 

Ferrohacillus 227 

Photobacterium 193 

Selenomonas 258 

Myconostoc 260 

Pasteurella 395 

Euhacterium 552 

Catenabacterium 560 

Ramibacterium 563 

Vilreoscillaceae 844 

Arthrobacter 605 

Clostridium 634 

Clostridium 634 

Pasteurella 395 

Vibrio 229 

Corynebacterium 579 

Enter obacteriaceae 332 

Moraxella 419 

Bacteroidaceae 423 

Neisseria 480 

Lactobacillaceae 505 

Diplococcus 507 

Corynebacterium 579 

Listeria 597 

Anaplasma 981 

Mycococcus 707 

Lactobacillaceae 505 

Streptococcus 508 

Microcyclus 253 

Thiobacillus 83 

Lactobacillaceae 505 

Pediococcus 529 

Leuconostoc 531 

Lactobacillus 542 

Neisseria 480 

Veillonella 485 

Caryophanales 830 

Microtatobiotes 931 and 933 

Rickettsiales 934 

Anaplasmataceae 980 

Bordetella 402 

Haemophilus 406 

Vilreoscillaceae 844 



t Deceased. 



Vlll 



LIST OF CONTRIBUTORS 



Rake, Geoffrey W. 
Reed, Guilford B.f 
Robinson, Elliott S. 
Robinson, George H.f 
Schatz, Albert 
Seeley, H. W. 
Seeliger, H. 
Sherman, James W.f 

Skerman, V. B. D. 

Smit, Jan 

Smith, Louis DeSpain 

Smith, N. R. 

Snieszko, S. F. 
Spray, R. S. 
Stanier, R. Y. 
Starkey, R. L. 
Steinhaus, E. A. 
Stuart, C. A. 
Temple, Kenneth L. 
Thj0tta, Th.t 

Tobie, W. C. 
van Niel, C. B. 



Vaughn, Reese 
Verona, Onorato 
Waksman, S. A. 



Wattie, Elsie (Mrs. 
Lackey) 

Weeks, Owen B. 
Weinman, David 
Wolff, J. W. 
Yale, N. W. 

ZoBell, Claude E. 



Chlamydiaceae 957 

Mycobacterium 695 

Diplococcus 507 

Spirochaetales 892 

Hydrogenomonas facilis 76 

Streptococcus 508 

Corynebacterium 579 

Lactobacillaceae 505 

Streptococcus 508 

Artificial Keys 987 

Sarcina 467 

Lactobacillaceae 505 

Peptostreptococcus 533 

Bacteroidaceae 423 

Bacillus 613 

Aeromonas 189 

Clostridium 634 

Myxobacterales 854 

Nitrobacteraceae 68 

Virales 985 

Proteus 364 

Thiobacillus 83 

Alginornonas 202 

Alginobacter 348 

Chromobacterium 292 

Rhodobacteriineae 35 

Propionibacterium 569 

Achromatiaceae 851 

Acetobacter 183 

Cellvibrio 250 

Actinomycetales 694 

Mycococcus 707 

Actinomycetaceae 713 

Streptomycetaceae 744 

Zoogloea 206 

Spirochaetales 892 

Flavobacterium 309 

Bartonellaceae 968 

Leptospira 907 

Escherichia 335 

Aerobacter 341 

Desulfovibrio 248 



t Deceased. 



PREFACE TO SEVENTH EDITION 

The general format of the seventh edition of Bergey's Manual of Deter- 
minative Bacteriology differs but Uttle from that of the sixth edition. How- 
ever, examination will reveal many changes in the content as the result of a 
thoroughgoing revision. Among these the following seem to be worthy of special 
comment. 

The most obvious change is that of the separation into two volumes of the 
material comparable to that which appeared in the sixth edition. The present 
volume is entitled the seventh edition of Bergey's Manual of Determinative 
Bacteriology. This Manual contains an outlined classification of the bac- 
teria and the descriptions of the taxa from Class to Species and Subspecies, to- 
gether with the appropriate keys. Nearly all species regarded as having been 
inadequately described or that could not be definitely placed have been excluded, 
together with many of the less important synonyms of the accepted species. 
These, together with the index to all the literature of both accepted and poorly 
described organisms have been transferred to a volume to be known as the 
Index Bergeyana. The latter volume will include all descriptions and citations 
to species formerly found as appendices or indefinitely placed as species incertae 
sedis. The host and habitat index will also be found in the Index Bergeyana. 
The net result is that the Manual itself contains descriptions of many more 
species with more adequate descriptions than have former editions; the transfer 
of much material to the Index Bergeyana has meant a reduction in the number 
of pages and a book of more convenient size and greater usefulness. The Index 
Bergeyana should prove to be an invaluable tool for the research microbiologist, 
containing, as it will, references to the whole field of systematic bacteriology and 
an index to the names of described species, both valid and invalid. 

Much material of historical value and interest in the sixth and earlier editions 
of the Manual has been excluded, not because it is lacking in real value to the 
student, but because repetition of its publication is now unnecessary. 

This edition of the Manual represents the coordinated results of the work of 
one hundred contributors, about thirty-five more than assisted in preparing the 
sixth edition. The contributors to the Manual are to be regarded in all nomen- 
clatural matters as strictly the authors of their sections. All new names of taxa 
and the names of all new combinations are to be ascribed to these authors, and 
not to the editors of the Manual. Contributors from countries other than the 
United States are more numerous than in the earlier editions. In other words, 
the Manual is rapidly assuming the character of an international publication. 
To all of these contributors the sincere thanks of the Board of Editors, and par- 
ticularly of the Editor-in-Chief, are due. The seventh edition is a tribute to the 
patience, care and scientific acumen of these individuals. Special note should be 
taken of the assistance rendered in the office of the Editor-in-Chief by Mr. 
Erwin Lessel, Miss Maude Hogan, Mrs. Eleanore Heist CUse and Mrs. Margaret 
Edson Breed. 



X PREFACE TO SEVENTH EDITION 

The keys to the several categories of taxa (orders, families, tribes, genera and 
species) have been revised with a view to making them more reUable and useful. 
There is included also an artificial key to the species prepared by Professor 
V. B. D. Skerman, which key should prove helpful. 

The Section on Nomenclature, including a synopsis of the Botanical Code of 
Nomenclature, has been eliminated. At the time of preparation of the sixth 
edition, the International Code of Bacteriological Nomenclature had not been 
finally approved, and emphasis was properly laid upon the rules used in Botany. 
This is no longer pertinent. The Bacteriological Code appeared in 1948 too late 
for use in making appropriate revisions in the 6th Edition of the Manual. The 
revised International Code of Nomenclature of the Bacteria and Viruses is about 
to be published. This contains annotations that should prove of value to the 
student, and should be regarded as a helpful aid in the understanding of the 
nomenclature used in the 7th Edition of the Manual. 

The naming and classification of the viruses, as published in the sixth edition 
of the Manual, was regarded by some eminent virologists as perhaps inadvisable 
because it was premature. They felt strongly that the problems of morphology, 
physiology, pathogenesis and inter-relationships of the viruses were not as yet 
sufficiently resolved to make satisfactory taxonomy and classification practicable. 
After consultation with the International Subcommittee on Viruses it was de- 
cided that the Virus Section should not be included in the seventh edition. This 
deletion has been made with the full expectation that sufficient international 
agreement will be reached to make possible adequate treatment in the eighth 
edition. The Editorial Committee recognizes that a satisfactory system of 
nomenclature and taxonomy for the viruses is imperative. 

The Editors wish to repeat and emphasize a statement made in the Preface 
of the first edition of the Manual: 

"The assistance of all bacteriologists is earnestly solicited in the correction of possible 
errors in the text." 

Among the tasks of the several editions of the Manual has been the codification 
of an increasingly satisfactory classification of the bacteria and the correction of 
the nomenclature of the past. The present volume undoubtedly has many errors 
that were not caught notwithstanding a most earnest effort. There are also many 
unresolved questions. Inasmuch as this volume appears at almost the same time 
as the Revised International Bacteriological Code, there are doubtless still some 
inconsistencies. 

E. G. D. Murray 
N. R. Smith 
R. S. Breed, Chairman 
Editorial Committee 



PREFACE TO SEVENTH EDITION XI 

NOTE 

The Board of Trustees of Bergey's Manual wish to record their profound 
sorrow at the death on February 10, 1956, of Dr. Robert S. Breed, Chairman of 
the Board of Trustees and Editor-in-Chief of the Manual. Most regrettable is 
the fact that he did not live to see in printed form the results of his untiring 
and devoted labor. At the time of his death, most of the manuscript for the 
seventh edition had been placed in the hands of the publisher; the remainder was 
in such shape that it could be promptly submitted. The Board of Trustees of 
the Bergey Trust, including the Board of Editors, wish to pay tribute to the 
devotion, energy and skill of Dr. Breed over a period of many years, as shown 
in the organization of better bacterial nomenclature and classification. The 
science of microbiology is his debtor. 

Reconciliation of the nomenclature used in the seventh edition of the Manual 
with the provisions of the revised International Code of Nomenclature of the 
Bacteria and Viruses had not been entirely completed by Dr. Breed. As far as 
possible, these discrepancies have been corrected before publication. 

The death of Dr. Breed leaves the Editorial Committee without a chairman 
and editor-in-chief. The Board of Trustees is unanimous in the belief that a suc- 
cessor to Dr. Breed should be found outside its present membership. Dr. Breed 
was also Chairman of the Board of Trustees. Following his death, reorganization 
of the Board was undertaken by Dr. Conn, as Treasurer, and Dr. Buchanan was 
designated as Chairman. The latter has agreed to serve until publication of the 
seventh edition of Bergey's Manual and of the first edition of the companion 
volume, planned by Dr. Breed and christened by him the Index Bergeyana. 
It is recognized to be a matter of urgency and diflficulty to replace Dr. Breed 
with an editor-in-chief for the eighth edition and to find a means of making this 
onerous responsibility something more than the labor of love it always was to him. 

E. G. D. Murray 
N. R. Smith 
H. J. Conn 

R. E. Buchanan, Chairman 
Board of Trustees 



PREFACE OF FIRST EDITION 

The elaborate system of classification of the bacteria into families, tribes 
and genera by a Committee on Characterization and Classification of the 
Society of American Bacteriologists (1917, 1920) has made it very desirable 
to be able to place in the hands of students a more detailed key for the 
identification of species than any that is available at present. The valuable 
book on "Determinative Bacteriology" by Professor F. D. Chester, pub- 
lished in 1901, is now of very little assistance to the student, and all previous 
classifications are of still less value, especially as earlier systems of classifica- 
tion were based entirely on morphologic characters. 

It is hoped that this manual will serve to stimulate efforts to perfect the 
classification of bacteria, especially by emphasizing the valuable features 
as well as the weaker points in the new system which the Committee of the 
Society of American Bacteriologists has promulgated. The Committee 
does not regard the classification of species offered here as in any sense 
final, but merely a progress report leading to more satisfactory classification 
in the future. 

The Committee desires to express its appreciation and thanks to those 
members of the society who gave valuable aid in the compilation of material 
and the classification of certain species. . . . 

The assistance of all bacteriologists is earnestly solicited in the correction 
of possible errors in the text ; in the collection of descriptions of all bacteria 
that may have been omitted from the text; in supplying more detailed 
descriptions of such organisms as are described incompletely; and in furnish- 
ing complete descriptions of new organisms that may be discovered, or in 
directing the attention of the Committee to publications of such newly 
described bacteria. 

David H. Bergey, Chairman 
Francis C. Harrison 
Robert S. Breed 
Bernard W. Hammer 
Frank M. Huntoon 
Committee on Manual. 
August, 1923. 



CONTENTS 

Introduction 1 

Considerations Influencing the Classification Used in This Edition of the Manual. ... 4 

How Bacteria are Named and Identified 15 

Division I. Protophyta Sachs, 1874, cviend. Krassilnikov, 1949 29 

Class I. Schizophyceae Cohn, 1879 30 

Class II. Schizomycetes von Naegeli, 1857 33 

Order I. Pseudomonadales Orla-Jensen, 1921 35 

Suborder I. Rhodohacteriineae Breed, Murray and Kitchens, 1944 35 

Family I. Thiorhodaceae Molisch, 1907 38 

Genus I. Thiosarcina Winogradsky, 1888 39 

Genus II. Thiopedia Winogradsky, 1888 40 

Genus III. Thiocapsa Winogradsky, 1888 41 

Genus IV. Thiodiclyon Winogradsky, 1888 41 

Genus V. Thioihece Winogradsky, 1888 42 

Genus VI. Thiocyslis Winogradsky, 1888 42 

Genus VII. Lamprocystis Schroeter, 1886 43 

Genus VIII. Amoebobacter Winogradsky, 1888 44 

Genus IX. Thiopolycoccus Winogradsky, 1888 45 

Genus X. Thiospirillum Winogradsky, 1888 46 

Genus XI. Rhabdomonas Cohn, 1875 48 

Genus XII. Rhodolhece Molisch, 1907 50 

Genus XIII. Chromatium Perty, 1852 50 

Family II. A thiorhodaceae Molisch, 1907 53 

Genus I. Rhodopseudomonas Kluyver and van Niel, 1937, emend, van 

Niel, 1944 53 

Genus II. Rhodospirillum Molisch, 1907, emend, van Niel, 1944 58 

Family III. Chlorobacteriaceae Lauterborn, 1913 61 

Genus I. Chlorobium Nadson, 1912 62 

Genus II. Pelodictyon Lauterborn, 1913 63 

Genus III. Clathrochloris Geitler, 1925 64 

Genus IV. Chlorobacterium Lauterborn, 1915 65 

Genus V. Chlorochromatium Lauterborn, 1906 65 

Genus VI. Cylindrogloea Perfiliev, 1914 66 

Suborder II. Pseudomonadineae Breed, Murray and Smith, sub-ordo nov 67 

Family I. Nitrobacteraceae Buchanan, 1917 68 

Genus I. Nitrosomonas Winogradsky, 1890 68 

Genus II. Nitrosococcus Winogradsky, 1892 69 

Genus III. Nitrosospira Winogradsky, 1931 70 

Genus IV. Nitrosocystis Winogradsky, 1931 70 

Genus V. Nitrosogloea H. Winogradsky, 1935 71 

Genus VI. Nitrobacter Winogradsky, 1892 72 

Genus VII. Nitrocystis H. Winogradsky, 1935 73 

Family II. Methanomonadaceae Breed, fam. nov 74 

Genus I. Methanomonas Orla-Jensen, 1909 74 

Genus II. Hydrogenomonas Orla-Jensen, 1909 75 

Genus III. Carboxydomonas Orla-Jensen, 1909 77 

Family III. Thiobacteriaceae Janke, 1924 78 

Genus I. Thiobaclerium Janke, 1924 79 

Genus II. Macromonas Utermohl and Koppe, 1923 80 

Genus III. Thiovulum Hinze, 1913 81 

xiii 



'^'3664 



CONTENTS 



Genus IV. Thiospira Vislouch, 1914 82 

Genus V. Thiobacillus Beijerinck, 1904 83 

Family IV. Pseudomonadaceae Winslow et al., 1917 88 

Genus I. Pseudomonas Migula, 1894 89 

Genus II. Xanthomonas Dowson, 1939 152 

Genus III. Acetobacier Beijerinck, 1898 183 

Genus IV. Aeromonas Kluyver and van Niel, 1936 189 

Genus V. Photohacterium Beijerinck, 1889, emend. Breed and Lessel, 

1954 193 

Genus VI. Azotomonas Stapp, 1940 198 

Genus VII. Zymomonas Kluyver and van Niel, 1936 199 

Genus VIII. Protaminobacter den Dooren de Jong, 1926 200 

Genus IX. Alginomonas Thj0tta and K&ss, 1945 202 

Genus X. Mycoplana Gray and Thornton, 1928 204 

Genus XI. Zoogloea Cohn, 1854 206 

Genus XII. Halobacterium Elazari-Volcani, 1940 207 

Family V. Caulobacteraceae Henrici and Johnson, 1935, emend. Breed 212 

Genus I. Caulobacter Henrici and Johnson, 1935 213 

Genus II. Gallionella Ehrenberg, 1838 214 

Genus III. Siderophacus Beger, 1944 216 

Genus IV. Nevskia Famintzin, 1892 216 

Family VI. Siderocapsaceae Pribram, 1929 217 

Genus I. Siderocapsa Molisch, 1909 218 

Genus II. Siderosphaera Beger, 1944 220 

Genus III. Sideronema Beger, 1941 220 

Genus IV. Ferribacterium Brussoff , 1916 221 

Genus V. Sideromonas Cholodny, 1922 222 

Genus VI. N aumanniella Dorff, 1934 223 

Genus VII. Ochrobium Perfiliev, 1921 225 

Genus VIII. Siderococcns Dorff, 1934 225 

Genus IX. Siderobacter Naumann, 1922 226 

Genus X. Ferrobacillus Leathen and Braley, 1954 227 

Family VII. Spirillaceae Migula, 1894 228 

Genus I. Vibrio Miiller, 1773 229 

Genus II. Desulfovibrio Kluyver and van Niel, 1936 248 

Genus III. Methanobacterium Kluyver and van Niel, 1936 250 

Genus IV. Cellvibrio Winogradsky, 1929 250 

Genus V. Cellfalcicula Winogradsky, 1929 252 

Genus VI. Microcyclus 0rskov, 1928 253 

Genus VII. Spirillum Ehrenberg, 1832 253 

Genus VIII. Paraspirillum Dobell, 1912 257 

Genus IX. Selenomonas von Prowazek, 1913 258 

Genus X. Myconostoc Cohn, 1875 260 

Order II. Chlamydobacteriales Buchanan, 1917 262 

Family I. Chlamydobacteriaceae Migula, 1894 262 

Genus I. Sphaerotilus Kiitzing, 1833 263 

Genus II. Leptothrix Kiitzing, 1843 264 

Genus III. Toxothrix Molisch, 1925 269 

Family II. Peloplocaceae Beger, fam. nov 270 

Genus I. Peloploca Lauterborn, 1913 270 

Genus II. Pelonema Lauterborn, 1915 271 

Family III. Crenotrichaceae Hansgirg, 1888 272 

Genus I. Crenothrix Cohn, 1870 272 



CONTENTS XV 

Genus II. Phragmidiothrix Engler, 1883 273 

Genus III. Clonothrix Roze, 1896 274 

Order III. Hyphomicrobiales Douglas, ordo nov 276 

Family I. Hyphomicrobiaceae Babudieri, 1950 276 

Genus I. Hyphomicrobimn Stutzer and Hartleb, 1898 277 

Genus II. Rhodomicrobium Duchow and Douglas, 1949 277 

Family II. Pasteuriaceae Laurent, 1890, emend. Henrici and Johnson, 1935. . 278 

Genus I. Pasteuria MetchnikofT, 1888 279 

Genus II. Blasiocaulis Henrici and Johnson, 1935 279 

Order IV. Enbacteriales Buchanan, 1917 281 

Family I. Azotobacteraceae Bergey, Breed and Murray, 1938 283 

Genus I. Azotobacter Beijerinck, 1901 283 

Family II. Rhizobiaceae Conn, 1938 .' 285 

Genus I. Rhizobium Frank, 1889 285 

Genus II. Agrobacterium Conn, 1942 288 

Genus III. Chromobacterium Bergonzini, 1881 292 

Family III. Achromobacteraceae Breed, 1945 296 

Genus I. Alcaligenes Castellani and Chalmers, 1919 297 

Genus II. Achromobacter Bergey et al., 1923 300 

Genus III. Flavobacteriurn Bergey et al., 1923 309 

Genus IV. Agarbacterium Angst, 1929 322 

Genus V. Beneckea Campbell, gen. nov 328 

Family IV. Enterobacteriaceae Rahn, 1937 332 

Tribe I. Escherichieae Bergey, Breed and Murray, 1938 334 

Genus I. Escherichia Castellani and Chalmers, 1919 335 

Genus II. Aerobacter Beijerinck, 1900 341 

Genus III. Klebsiella Trevisan, 1885 344 

Genus IV. Paracolobactrum Borman, Stuart and Wheeler, 1944 346 

Genus V. Alginobacter Thj0tta and Kiss, 1944 348 

Tribe II. Erwinieae Winslow et al., 1920 349 

Genus VI. Erwinia Winslow et al., 1917 349 

Tribe III. Serratieae Bergey, Breed and Murray, 1938 359 

Genus VII. Serratia Bizio, 1823, emend. Breed and Breed, 1927 359 

Tribe IV. Proteeae Castellani and Chalmers, 1919 364 

Genus VIII. Proteus Hauser, 1885 364 

Tribe V. Salmonelleae Bergey, Breed and Murray, 1938 368 

Genus IX. Salmonella Lignieres, 1900 368 

Genus X. Shigella Castellani and Chalmers, 1919 384 

Family V. Brucellaceae, nom. nov 394 

Genus I. Pasteurella Trevisan, 1887 395 

Genus II. Bordetella Moreno-Lopez, 1952 402 

Genus III. Brucella Meyer and Shaw, 1920 404 

Genus IV. Haemophilus Winslow et al., 1917 406 

Genus V. Actinobacillus Brumpt, 1910 414 

Genus VI. Calymmatobacterium Aragao and Vianna, 1913 418 

Genus VII. Moraxella Lwoff, 1939 419 

Genus VIII. Noguchia Olitsky, Syverton and Tyler, 1934 421 

Family VI. Bacteroidaceae Breed, Murray and Smith, fam. nov 423 

Genus I. Bacieroides Castellani and Chalmers, 1919 424 

Genus II. Fusobacterium Knorr, 1922 436 

Genus III. Dialister Bergey et al., 1923 440 

Genus IV. Sphaerophorus Pr6vot, 1938 441 

Genus V. Streptobacillus Levaditi, Nicolau and Poincloux, 1925 451 



XVI CONTENTS 

Family VII. Micrococcaceae Pribram, 1929 454 

Genus I. Micrococcus Cohn, 1872 455 

Genus II. Staphylococcus Rosenbach, 1894 464 

Genus III. Gaffkya Trevisan, 1885 466 

Genus IV. Sarcina Goodsir, 1842 467 

Subgenus I. Zyniosarcina Smit, 1930 468 

Subgenus II. Methanosarcina Kluyver and van Niel, 1936 468 

Subgenus III. Sarcinococcus Breed, 1948 468 

Subgenus IV. Urosarcina Miquel, 1888 468 

Genus V. Methanococcus Kku'ver and van Niel, 1936, emend. Barker, 

1936 473 

Genus VI. Peptococcus Kluyver and van Niel, 1936 474 

Family VIII. Neisseriaceae Prevot, 1933 480 

Genus I. Neisseria Trevisan, 1885 480 

Genus II. Veillonella Prevot, 1933 485 

Family IX. Brevibacteriaceae Breed, 1953 490 

Genus I. Brevibacterium Breed, 1953 490 

Genus II. Kiirthia Trevisan, 1885 503 

Family X. Lactobacillaceae Winslow et al., 1917 505 

Tribe I. Streptococceae Trevisan, 1889 506 

Genus I. Diplococcus Weichselbaum, 1886 507 

Genus II. Streptococcus Rosenbach, 1884 508 

Genus III. Pediococcus Balcke, 1884, e77iend. Mees, 1934 529 

Genus IV. Leuconostoc van Tieghem, 1878, eviend. Hucker and Pederson, 

1930 531 

Genus V. Peptostreptococcus Kluyver and van Niel, 1936 533 

Tribe II. Laciobacilleae Winslow et al., 1920 541 

Genus I. Lactobacillus Beijerinck, 1901 542 

Subgenus I. Lactobacillus Beijerinck, 1901 543 

Subgenus II. Saccharobacillus van Laer, 1892 543 

Genus II. Eubacterium Prevot, 1938 552 

Genus III. Catenabacterium Prevot, 1938 560 

Genus IV. Ramibacterium Prevot, 1938 563 

Genus V. Cillobacterium Prevot, 1938 566 

Family XI. Propionibacteriaceae Delwiche, jam. nov 569 

Genus I. Propionibacterium Orla-Jensen, 1909 569 

Genus II. Butijribacterium Barker and Haas, 1944 577 

Genus III. Zymohacterium Wachsman and Barker, 1954 577 

Family XII. Corynebacteriaceae Lehmann and Neumann, 1907 578 

Genus I. Corynebacterium Lehmann and Neumann, 1896 579 

Genus II. Listeria Pirie, 1940 597 

Genus III. Erysipelothrix Rosenbach, 1909 599 

Genus IV. Microbacterium Orla-Jensen, 1919 600 

Genus V. Cellulomonas Bergey et al., 1923, emend. Clark, 1952 601 

Genus VI. Arthrobacter Fischer, 1895, emend. Conn and Dimmick, 1947. . 605 

Family XIII. Bacillaceae Fischer, 1895 613 

Genus I. Bacillus Cohn, 1872 613 

Genus II. Clostridium Prazmowski, 1880 634 

*Order V. Actinomycetales Buchanan, 1917 694 

* Erratum: Due to a clerical error the orders Caryophanales and Actinomycetes of the 

class Schizomycetales appear in the wrong sequence in numerous places throughout the 
MANUAL: correctly, Caryophanales is Order V and should appear before Order VI, Acti- 
nomycetales (see pages 12, 33, and 34 for reasons why Caryophanales precedes Actinomyce- 
tales in the classification scheme). 



CONTENTS XVll 

Family I. Mycobacteriaceae Chester, 1901 695 

Genus I. Mycobacterium Lehmann and Neumann, 1896 695 

Genus II. Mycococcus Krassilnikov, 1938 707 

Family II. Actinomyceiaceae Buchanan, 1918 713 

Genus I. Nocardia Trevisan, 1889 713 

Genus II. Actinomyces Harz, 1877 742 

Family III. Streptonrycctaceae Waksman and Henrici, 1943 744 

Genus I. Streptomyces Waksman and Henrici, 1943 744 

Genus II. Micromunospora ^rskov, 1923 822 

Genus III. Thermoactinomyces Tsiklinsky, 1899 824 

Family IV. Aciinoplanaceae Couch, 1955 825 

Genus I. Actinoplanes Couch, 1950 826 

Genus II. Streptosporangiurn Couch, 1955 828 

Order VI. Caryophanales Peshkoff, 1940 830 

Family I. Caryophanaceae Peshkoff, 1940 830 

Genus I. Caryophanon Peshkoff, 1940 831 

Genus II. Lineola Pringsheim, 1950 832 

Genus III. SimonsieUa Schmid, 1922 833 

Family II. Oscillospiraceae Peshkoff, 1940 834 

Genus I. Oscillospira Chatton and Perard, 1913 834 

Family III. Arthromitaceae Peshkoff, 1940 835 

Genus I. Arthromitus Leidy, 1849 835 

Genus II. Coleomitus Duboscq and Grasse, 1930 836 

Order VII. Beggiatoales Buchanan, ordo nov 837 

Family I. Beggiatoaceae Migula, 1894 837 

Genus I. Beggiatoa Trevisan, 1842 838 

Genus II. Thiospirillopsis Uphof, 1927 840 

Genus III. Thioploca Lauterborn, 1907 841 

Genus IV. Thiothrix Winogradsky, 1888 842 

Family II. Vitreoscillaceae Pringsheim, 1949 844 

Genus I. Vitreoscilla Pringsheim, 1951 845 

Genus II. Bactoscilla Pringsheim, 1951 848 

Genus III. MicrosciUa Pringsheim, 1951 849 

Family III. Leucotrichaceae Buchanan, farn. nov 850 

Genus I. Leucothrix Oersted, 1844, emend. Harold and Stanier, 1955. . . . 850 

Family IV. Achromatiaceae Massart, 1902 851 

Genus I. Achromatiiim Schewiakoff, 1893 852 

Order VIII. Myxobacterales Jahn, 1915 854 

Family I. Cytophagaceae Stanier, 1940 858 

Genus I. Cytophaga Winogradsky, 1929 858 

Family II. Archangiaceae Jahn, 1924 863 

Genus I. Archangium Jahn, 1924 863 

Genus II. Stelangium Jahn, 1915 866 

Family III. Sorangiaceae Jahn, 1924 866 

Genus I. Sorangium Jahn, 1924 866 

Family IV. Polyangiaceae Jahn, 1924 870 

Genus I. Polyangium Link, 1809 870 

Genus II. Synangium Jahn, 1924 877 

Genus III. Podangium Jahn, 1924 877 

Genus IV. Chondrojnyces Berkeley and Curtis, 1874 879 

Family V. Myxococcaceae Jahn, 1924 882 

Genus I. Myxococcus Thaxter, 1892 883 

Genus II. Chondrococcus Jahn, 1924 886 



XVlll CONTENTS 

Genus III. Angiococcus Jahn, 1924 889 

Genus IV. Sporocytophaga Stanier, 1940 890 

Order IX. Spirochaeiales Buchanan, 1918 892 

Family I. Spirochaetaceae Swellengrebel, 1907 892 

Genus I. Spirochaeta Ehrenberg, 1833 893 

Genus II. Saprospira Gross, 1911 894 

Genus III. Cristispira Gross, 1910 895 

Family II. Treponemataceae Robinson, 1948 896 

Genus I. Borrelia Swellengrebel, 1907 897 

Genus II. Treponema Schaudinn, 1905 904 

Genus III. Leptospira Noguchi, 1917 907 

Order X. Mycoplasmaiales Freundt, 1955 914 

Family I. Mycoplasmaiaceae Freundt, 1955 914 

Genus I. Mycoplasma Nowak, 1929 914 

Addendum to Class II, Schizomycetes von Naegeli. Bacteria symbiotic or parasitic 

in protozoa 926 

Class III. Microtatobiofes Philip, 1956 931 and 933 

Order I. iSz'c^^eWsmZes Buchanan and Buchanan, 1938, emend. Gieszczykiewicz, 1939 934 

Family I. Rickettsiaceae Pinkerton, 1936 934 

Tribe I. Rickettsieae Philip, trib. nov 935 

Genus I. Rickettsia da Rocha-Lima, 1916 935 

Subgenus A. Rickettsia Philip, 1943 937 

Subgenus B. Zinssera Macchiavello, 1947 939 

Subgenus C. Dermacentroxenus (Wolbach, 1919) Philip, 1943 941 

Subgenus D. Rochalimaea Macchiavello, 1947 945 

Genus II. Coxiella Philip, 1948 947 

Tribe II. Ehrlichieae Philip, trib. nov 948 

Genus III. Ehrlichia Moshkovskiy, 1945 949 

Genus IV. Cowdria Moshkovskiy, 1945 950 

Genus V. Neorickettsia Philip et al., 1953 951 

Tribe III. Wolbachieae Philip, 1956 952 

Genus VI. Wolbachia Hertig, 1936 953 

Genus VII. Symhiotes Philip, 1956 956 

Genus VIII. Rickettsiella Philip, 1956 957 

Family II. Chlamydiaceae Rake, fam. nov 957 

Genus I. Chlamydia Rake, 1956 958 

Genus II. Colesiota Rake, 1948 959 

Genus III. Ricolesia Rake, gen. nov 959 

Genus IV. Colettsia Rake, nom. nov 961 

Genus V. Miyagawanella Brumpt, 1938 961 

Family III. Bartonellaceae Gieszczykiewicz, 1939 968 

Genus I. Bartonella Strong, Tyzzer and Sellards, 1915 969 

Genus II. Grahariiella Brumpt, 1911 971 

Genus III. Haemobartonella Tyzzer and Weinman, 1939 972 

Genus IV. Eperythrozoon Schilling, 1928 977 

Family IV. Anaplasmataceae Yakimov, 1931 980 

Genus I. Anaplasma Theiler, 1910 981 

Order II. Virales Breed, Murray and Kitchens, 1944 985 

Artificial Key 987 

Index of Genera and Species 1093 



INTRODUCTION 

Suggestions for the Use of the Manual In Classifying 
Unknown Organisms 

No organism can be classified before its morphological, cultural, physiological 
and pathogenic characters have been determined through a detailed study. 

The characters used in the keys to orders, families and genera may ordinarily 
be determined by the use of a dozen or more of the procedures described in the 
]\Ianual of Microbiological Methods issued by the Committee on Bacteriological 
Technic of the Society of American Bacteriologists. More complete examinations 
are required in special cases to identify and to describe individual species ne- 
cessitating resort to the original literature. When those prevailing are inad- 
equate, new criteria are desirable. This desideratum extends to some higher taxa 
to achieve more exact and distinctive definitions. 

It is urged that beginning students be taught all of the techniques necessary 
for the identification of species in the hope that the taxonomic work of the future 
may be placed on a satisfactory basis. 

After a complete study of the characters of the organism has been made, 
either of two courses may be followed. (1) Use the Keys in the body of the text 
as explained below. These follow what are believed to be the natural relationships 
that exist between various groups of bacteria. (2) The beginning student may, 
however, find the artificial key at the back of the Manual to be more helpful 
than the natural keys in determining the identity of an unknown culture. 

In all cases it should be kept in mind that many descriptions of species of 
bacteria are not mentioned in this Manual. Failure to find agreement between 
an unknown culture and any of the descriptions given in this Manual does not 
prove that the unknown culture represents a species that has never been studied 
and described. 

If the student wishes to follow through the natural keys he should turn to 
page 33 and ascertain first in which order the organism belongs. When the 
order has been ascertained, turn to the page of the Manual on which the key to 
that order is given. In this key ascertain the family or sub-family to which the 
organism belongs. 

When the family has been determined, again refer to the page of the Manual 
on which the key to that family is given. In this key ascertain the tribe to which 
the organism belongs. 

When the tribe has been determined, again find the page of the Manual on 
which the key to the tribe is given. In this key ascertain the genus to which the or- 
ganism belongs. 

When the genus has been determined, again refer to the page of the Manual 
on which the key to that genus is given. In this key trace out the species under 
investigation. 

1 



2 SUGGESTIONS FOR USE OF THE MANUAL 

For example, if one wishes to identify a short, peritrichous. Gram-negative, 
non-spore-forming, non-chromogenic rod that grows well on ordinary culture 
media at 37 °C., fermenting glucose and lactose with the production of acid and 
gas, not liquefying gelatin, with negative reaction for acetylmethylcarbinol, 
citrate-negative, alginate-negative, pectinase-negative, producing indole and 
reducing nitrates, consult the key to the orders on page 33. 

In this key examine I: Cells rigid. Motile by means of polar flagella or non-motile. 
This does not indicate our organism, which is peritrichous. We turn next to II: 
Not as above. Under A: Cells rigid. Spherical or straight, rod-shaped cells. Occur 
singly, in chains or in trichomes. Motile by means of peritrichous flagella or non- 
motile. These characters agree with those of the organism in question. 

We turn now to 1, in the same key: Cells spherical or rod-shaped. No trichomes, 
though chains of cells may occur. This indicates that the organism in question 
belongs in Order IV, Eubacteriales. 

In the key to the families of Order Eubacteriales, p. 281, examine I: Cells 
rod-shaped. Gram-negative. This indicates the organism in question, so we turn 
next to A: Aerobic or facultatively anaerobic, which again indicates the organism 
in question. 

The next entry, 1: Large, ovoid to rod-shaped cells, sometimes yeast-like in 
appearance. Free-living in soil. Fix free nitrogen, does not indicate the culture 
under study so we turn to 2 : Not as above. 

The heading, 2 : Heterotrophic rods which may not require organic nitrogen for 
growth. Usually motile, with one to six flagella. Frequently form nodules or tubercles 
on roots of plants or show violet chromogenesis. Colonies usually large and slimy, 
especially on mannitol agar, does not indicate the organism in question. We then 
turn to aa: Not as above. 

Heading b: Straight rods which grow readily on ordinary peptone media. May 
of may not ferment sugars anaerobically with the production of organic acids again 
indicates the culture under study. 

The heading c : Glucose usually attacked oxidatively or not at all does not indicate 
the organism in question as it is an active fermenter of glucose and lactose, 
cc: Ferment glucose anaerobically, frequently producing visible gas from glucose, and 
sometimes lactose indicates that the culture under study belongs in the Family IV, 
Enterobacteriaceae . 

We now turn to the key to the tribes of family Enterobacteriaceae, page 334. 
In this key we examine I: Lactose fermented anaerobically, usually within 48 hours. 
This indicates the culture under study. 

The entry A: Prodigiosin not produced also indicates the non-chromogenic 
organism in question. Likewise, 1: Do not produce protopectinase. Not parasitic 
on plants also applies to our culture, so we turn to the key to the genera of 
Tribe I, Escherichieae, page 335. 

We turn now to I: Alginic acid is not decomposed with the production of acid and 
gas. This likewise indicates the organism is question. Under this. A: Lactose is 
fermented within 48 hours also indicates the culture under study, as does 1: 



SUGGESTIONS FOR USE OF THE MANUAL 3 

Acetylmethylcarhinol not produced. Methyl red test positive. Salts of citric acid may 
or may not he used as a sole source of carbon. This places the organism in Genus I 
Escherichia. 

We turn now to the key to the species of Genus I, Escherichia, page 335. On 
tracing our organism in this key we find that its characters correspond with those 
of Escherichia coli and turn to the description of this species for a final confirma- 
tion of this identification. 

It is self evident that where the characters of the original culture have not 
been determined accurately or completely, the identity of the unknown can- 
not be determined positively. 

A second difficulty in the use of a key comes from inexperience in the use of 
technical terms; that is, the student may not thoroughly understand the meaning 
of the statement in the key and so cannot follow a route through the key with 
certainty. For example in the keys used here, the student must know the dif- 
ference between (1) chains of cells which are composed of dividing cells which 
do not separate at once, and (2) trichomes which are composed of dividing cells 
which remain more permanently together and are normally flattened against 
each other on adjacent sides. The trichomes may show some differentiation into 
holdfast cells and reproductive cells (conidia) . Both chains of cells and trichomes 
are to be distinguished from the mycelial threads found in Actinomycetaceae : the 
latter are unseptate and show true branching. 

The student should be warned not to take descriptions in the Manual too 
literally or too rigidly. Descriptions are usually drawn to represent average 
findings. Especially among bacteria, characters such as sugar fermentations, 
gelatin liquefaction, presence or absence of flagella and other things may vary 
within a species. Sometimes these variations are due to slight, possibly un- 
recognized variations in the techniques used in determining these characters. 
Real knowledge of the characteristics of species may also be very incomplete. 
This is true not only with respect to the physiological activities of these micro- 
organisms but also to such detectable structural features as the number and 
position of flagella. Dark-field movies of motile cells and photographs taken with 
the electron microscope are revealing new and heretofore unsuspected facts 
regarding structural features. 

Source and habitat data are frequently helpful in aiding the student to rec- 
ognize species of bacteria and may indicate that the pathogenicity of the culture 
in question may need to be tried on some specific animal or plant. By habitat 
is meant the kind of a place in which the organism normally grows; by source, 
the particular material and place from which the culture was obtained. This 
source may or may not indicate the natural habitat. The source of cultures is 
invariably more limited in scope than the habitat, as bacteria normally occur 
wherever their particular habitat may be found in a world-wide distribution. 



CONSIDERATIONS INFLUENCING THE CLASSIFICA- 
TION USED IN THIS EDITION OF THE MANUAL 

Robert S. Breed 

Cornell University, Geneva, New York 

The development of the classification systems used in the various editions of 
Bergey's Manual has caused those of us responsible for this work to give 
considerable thought to the probable evolutionary development of the living 
things that are included under the general terms bacteria and, more recently, 
viruses. 

For those who are not familiar with the principles of evolution, it might be 
well to bear in mind that all living things, including bacteria and viruses, do but 
represent the present form of a long line of ancestral forms. Customarily these 
lines of development are thought of as being not lineal but like the twigs and 
branches of a tree which trace their origin back to the trunk of the tree, living 
species being regarded as the separate and distinct tips of the twigs. 

Bacteria and viruses, endowed as they are with a simple morphology, are 
naturally thought of as being primordial or primitive in nature. This concept 
is fundamental in all systems of classification that have been developed for these 
organisms. Nevertheless it should not be forgotten that the different species or 
kinds of these morphologically simple living things now extant may have under- 
gone many types of changes during the course of their evolutionary development. 
However, because bacteria and viruses do not have hard parts that fossilize, 
there is little that can be learned about their evolution directly from historical 
geology (paleontology) . 

It is difficult to picture the environment under which the undifferentiated, 
unicellular organisms lived when they first appeared on the earth, but it is 
certain that this environment was quite different from the environment in which 
similar organisms live today. One important feature of the present-day envi- 
ronment that would have been lacking in the earliest periods would be the 
association of unicellular organisms with more highly developed types of living 
plants and animals and with the resultant accumulation of organic materials 
that must take place as the natural processes of life and death go forward. 
Organisms which are saprophytic and, still less, those which are parasitic would 
not have had conditions favorable for their existence in the earliest periods in 
which life developed on this planet. This makes it necessary to assume that the 
earliest living things must have existed on comparatively simple, largely inorganic 
food materials. With this thought in mind, some students of the systematic 
relationships of living things have thought of the chemoautotrophic bacteria 
that still exist as being more like primordial living things than are other types of 
bacteria. 



CONSIDERATIONS INFLUENCING CLASSIFICATION 5 

It is true that the chemoautotrophic organisms are able to Hve on simple 
inorganic foods that were, in all probability, available to living things under 
early conditions in the development of the earth. However, it does not necessarily 
follow that chemoautotrophic forms are the only ones that could have existed 
in the beginning. It seems even more reasonable to assume that early living 
forms developed a pigment like chlorophyll that enabled primordial bacteria to 
utilize the sun's energy in synthesizing organic matter. Such photosynthetic 
pigments are found in purple or green bacteria. These photoautotrophic forms 
could have existed on the simple foods available when life began as readily as 
could chemoautotrophic forms. 

In either case, it is necessary to assume that living protoplasm, with its com- 
plex enzymatic systems, existed before primordial bacteria, which utilized 
inorganic materials as food. In other words, complex proteins had to be in 
existence before either chemoautotrophic or photoautotrophic bacteria of the 
types now found on the earth could exist. 

Even if it is granted that photoautotrophic living things were primordial, it 
must also be granted that when the existence of such organisms is postulated 
we are not starting with the beginning of life itself. So little is known about the 
possibility of living proteins (protoplasm) developing out of inorganic com- 
pounds that speculation regarding this development has brought but very little 
information that is factual. 

In the present edition of Bergey's Manual, the classification used has been 
rearranged on the assumption that the photoautotrophic bacteria extant today 
presumably are the living organisms that are most nearly like the primordial 
types of bacteria. 

In support of this thought it should be kept in mind that the earliest living 
forms must necessarily have been free-living forms, not saprophytes nor parasites. 
This being the case, forms such as viruses that are very tiny in size and therefore 
necessarily of a simple structure ought not to be regarded as primitive just 
because of a comparatively simple structure. The viruses are adapted to life 
within living protoplasm, and they represent an extreme degree of specialization 
to a parasitic existence. They are known as organisms that invade the living cells 
of higher plants and animals, including man. The latter are the living things 
that were latest in development in geological time. Viruses could not have existed 
before their host plants and animals were developed. 

The term "viruses" ought not to be used for the hypothetical, very tiny, 
free-living primordial organisms that must have existed before primordial 
bacteria. Some investigators feel that such organisms may still exist in some as 
yet unrecognized form. 

It is not surprising that a great development has taken place in outline clas- 
sifications since bacteriologists first tried to develop such classifications to express 
the possible relationships of the organisms with which they have worked. While 
O. F. Mueller (Animalcula infusoria et Marina. Hauniae. 1786) and C. G. Ehren- 
berg (Die Infusionsthierchen als vollkommende Organismen. Leipzig, 1838) made 



6 CONSIDERATIONS INFLUENCING CLASSIFICATION 

simple beginnings along this line, their knowledge of bacteria as they are known 
today was very limited indeed. Even in 1838, when Ehrenberg published his 
description of the types of organisms found in infusions, microscopes had not 
yet been developed to a place where even large bacteria could be studied with 
any satisfaction. 

By 1872, Ferdinand Cohn (Untersuchungen iiber Bacterien. I. Beitr. z. Biol, 
d. Pflanzen., 1, Heft 2, 1872, 187-222), the botanist, began to understand that 
a great variety of types of bacteria were in existence, and he was able to arrange 
an outline classification on which later classifications of bacteria have been built. 
However, his first outline classification of bacteria was scarcely pubUshed before 
he felt that he should have expressed the relationships of the bacteria to the 
simplest types of algae in a more intimate way. He therefore, in 1875 (Unter- 
suchungen iiber Bacterien., II. ibid., 1, Heft 3, 1875, 141-207), drew up a second 
classification in which he integrated the known groups of bacteria with known 
groups of blue-green algae in a class, the Schizophyta. This arrangement assumed 
that the bacteria had a much more intimate relationship to the blue-green algae 
than the true fungi have to the green, red and brown algae. 

It should be noted that early classifications of bacteria were based primarily 
upon structural characters, particularly the shape of the cells. This was a 
natural development, as morphological characters had been found to be useful 
in drawing up natural classifications of higher plants and animals. It is also 
(luite natural that workers who drew up these classifications should have regarded 
the spherical organisms that they found as being primitive in nature. Little 
was known at that time of the distribution of bacteria in nature. It was not 
until later that it came to be realized that the bacteria that are spherical in 
shape are normally found on the skin or in secretions of skin glands (milk and 
other dairy products, etc.) of vertebrates. Few cocci exist as free-living forms in 
water or soil. Likewise, when physiological studies were made, it was found that 
the cocci require comparatively complex foods for their existence. Few modern 
classifications retain the arrangement in which cocci are placed first as suggested 
by Cohn in 1872. 

Others have developed the early classifications* drawn up by Cohn, with many 
individuals contributing to the development of a better and better understanding 
of the evolutionary development of the bacteria. In the 1890's, two groups 
of individuals undertook the publication of manuals describing the known species 
of bacteria. These two groups exercised a great influence on the development of 
systematic bacteriology. 

Migula (Arb. Bact. Inst., Karlsruhe, 1, 1894, 235-238; in Engler and Prantl, 
Naturlichen Pflanzenfamilien, Schizophyta, 1 Teil, la, 1895, 1-44) and his 
students began their work at Karlsruhe, Germany, in the early part of the 
1890's, publishing various papers and books, the last of which was Migula's 

* For a more detailed discussion of outline classifications developed by bacteriologists, 
3ee Manual, 3rd ed., 1930, 1-23; and Manual, 6th ed., 1948, 5-38. 



CONSIDERATIONS INFLUENCING CLASSIFICATION Y 

System der Bakterien (Bd. 1, 1897, 368 pp.; Bd. 2, 1900, 1068 pp., Jena). Only 
one edition was published. 

During the same period K. B. Lehmann and R. E. Neumann of Wiirzburg, 
Germany, began the publication of their Bakteriologische Diagnostik, the first 
edition of which was published, as were later editions, in two volumes (J. F. 
Lehmann Verlag, Miinchen). The first edition was soon followed by a second and 
later editions, the work being seriously interrupted by the first World War after 
the publication of the 5th edition. Following the war they republished the 5th 
edition with a supplement as the 6 edition and later carried through a complete 
revision of this text which appeared as the 7th edition in 1927. No further editions 
have been issued. 

In the meantime, interest in taxonomic work had crystallized in the newly 
organized (1899) Society of American Bacteriologists, led at first by F, D. 
Chester. His Manual of Determinative Bacteriology, published in 1901 (The 
MacMillan Co., New York), had great influence in guiding the thought of 
American bacteriologists, but it never has been widely known outside of North 
America. 

As the Society developed, others took an active interest in this work, among 
them R. E. Buchanan (Jour. Bact., 1, 1916, 591-596; 2, 1917, 155-164, 347-350, 
603-617; 3, 1918, 27-61, 175-181, 301-306, 403-406, 461-474, 541-545), who 
organized an outline classification of all bacteria as then known. This was pub- 
lished just as another member of the Society, C.-E. A. Winslow, who had, with 
his wife, completed a monographic study of the Coccaceae (Winslow, C. -E. A., and 
Winslow, A. R. Systematic relationships of the Coccaceae, 300 pp., 1908, John 
Wiley & Sons, New York), urged the Society to form a Committee to organize 
a better classification for bacteria. The Society of American Bacteriologists' 
Committee, of which Winslow was made Chairman, combined forces with Bu- 
chanan and published first a preliminary (Jour. Bact., 2, 1917, 505-566) and then 
a final report (Jour. Bact., 5, 1920, 191-229) on the classification of bacteria. The 
report of this Committee was accepted with the thought that further revisions 
of this outline classification were to be expected as knowledge developed. 

Meanwhile in Europe, Orla-Jensen (Cent. f. Bakt., II Abt., 22, 1909, 305-346) 
had made notable contributions to knowledge in this field. Still later A. J. Kluyver 
and C. B. van Niel (Zent. f. Bakt., II Abt., 34, 1936, 369-403) and others con- 
tinued the development of classifications of bacteria, but European workers have 
been badly handicapped in their work because of the chaotic conditions that 
have existed during two world wars fought largely in Europe. 

Developments in the field of systematic bacteriology led to the publication by 
D. H. Bergey of a manuscript on which he had been working for a long time, his 
thought being that a new edition of Chester's Manual of Determinative Bac- 
teriology was badly needed, as indeed it was. In order to aid Bergey in securing 
publication of his manuscript, the Society of American Bacteriologists appointed 
a Committee to assist him, Dr. F. C. Harrison, Chairman. The first edition of 



8 CONSIDERATIONS INFLUENCING CLASSIFICATION 

Bergey's Manual appeared in 1923 (The Williams & Wilkins Co., Baltimore). 
Successive editions of this Manual were issued in 1925, 1930 and 1936. Before 
his death in 1937, Bergey requested that an Editorial Board take over future 
editions of Bergey's Manual. 

At the same time, Bergey used the accumulated royalties that had previously 
been placed in the custody of the Society of American Bacteriologists to organize 
the so-called Bergey's Manual Trust. The publication of the 5th and 6th 
editions of Bergey's Manual has been carried out by the Trustees of this 
Trust, who, by the provisions of the Deed of Trust, must always be men trained 
as bacteriologists. The Board of Trustees consisted at first of Dr. D. H. Bergey, 
Professor R. S. Breed and Professor E. G. D. Murray. Dr. A. Parker Kitchens was 
elected to this Board after Dr. Bergey's death, when Professor Breed was made 
Chairman of the Board. 

Because of the truly enormous development of our knowledge of bacteria, 
viruses and related organisms, the Editorial Board asked students of special 
groups to assist in the revisions of the groups in which they were interested. 
Thus more than 40 specialists assisted in the preparation of the 5th edition, 
and more than 60 individuals in the preparation of the 6th edition of the Manual. 
Canadian bacteriologists as well as bacteriologists from the U. S. A. have 
participated in the Manual work from the beginning. This participation by 
Canadian workers has increased during the preparation of the manuscript for 
the 7th edition, as has the participation from other countries. Fourteen countries 
are represented among the more than 100 specialists who have contributed to 
the 7th edition of the Manual. 

After the death of Dr. A. Parker Hitchens, Dr. N. R. Smith was appointed 
to the Board of Trustees and to the Editorial Board of the Manual, and shortly 
thereafter the Board of Trustees was made a board of five members by the 
election of Dr. R. E. Buchanan and Dr. Harold J. Conn to this Board. 

In preparing manuscripts for the present edition of Bergey's Manual, 
specialists have found many places where the relationships of described species 
of bacteria have not been well presented in the literature. Consequently, they 
have been stimulated to publish many papers reporting their findings. The 
individual specialists have normally been persons who have actively worked 
with cultures of the organisms that belong to the group for which they have 
prepared the manuscript. Thus the development of the present edition of the 
Manual has stimulated much research in the field of S3^stematic bacteriology 
that would never have been accomplished under other conditions. It is hoped 
that in the future the Bergey's Manual Trust can become a center for research 
in the field of systematic bacteriology and virology. The work thus far accom- 
plished has been carried out largely by volunteer workers. If adequate funds were 
available for the support of such work its value could be greatly increased. 

Out of studies by specialists of the accumulated knowledge of the systematic 
relationships of the microorganisms considered in Bergey's Manual of Deter- 
minative Bacteriology, the three of us chiefly responsible for organizing this 



CONSIDERATIONS INFLUENCING CLASSIFICATION 9 

work (Professor R. S. Breed, Professor E. G. D. Murray and Dr. N. R. Smith) 
have developed an outline classification which expresses our ideas of the relation- 
ships of the simplest types of living things. These are represented by such common 
terms as true bacteria, filamentous bacteria, actinomycetes, slime bacteria, 
spirochetes, rickettsias and related larger viruses and the filterable viruses. This 
general classification also expresses our ideas of the relationships of these undif- 
ferentiated types of living things to higher plants. 

This outline may not express the views of other special students of this subject 
adequately, as all such outlines represent compromises between differing view- 
points. One such difference of viewpoint that has been discussed among the 
three of us chiefly responsible for the outline given here has been the question 
whether a third kingdom, the Protophyta as defined below, ought not to be 
recognized in addition to the Plant and Animal Kingdoms. Prof. E. G. D. Murray 
has been the one in our group who has felt most strongly that the bacteria and 
related organisms are so different from plants and animals that they should be 
grouped in a kingdom equal in rank with these kingdoms. It is quite probable 
that support for this viewpoint would be stronger if early biologists had known 
how different these important and widely diversified microorganisms are from 
plants and animals. Even today it must be recognized that our knowledge of the 
number of kinds of bacteria is growing rapidly as habitats not previously ade- 
quately explored are studied. The human body is, as a matter of fact, practically 
the only habitat that has been comprehensively studied as a source of bacteria. 
Even in this case it is the bacteria that cause diseases that are best known. 

Our knowledge of the still smaller types of parasitic and pathogenic organisms 
such as the numerous kinds of organisms found in the Rickettsiales and Virales 
is still more inadequate than our knowledge of the true bacteria. In fact our 
present-day knowledge of the filterable viruses could perhaps best be compared 
with Cohn's knowledge of the bacteria when he first drew up a system of classifi- 
cation for bacteria in 1872. 

Three groups are included in the outline presented here: (a) the blue-green 
algae, (b) bacteria and related forms, and (c) the rickettsias and viruses. 
These are placed in a single division of the plant kingdom for which the term 
Protophyta has been used. This name was suggested by a botanist, Sachs (Lehr- 
buch der Botanik, 4 Aufl., 926 pp., Wilhelm Engelmann, Leipzig). Recently 
Sachs' concept of this group has been developed further by a Russian system- 
atist, N. A. Krassilnikov (Guide to the Bacteria and Actinomycetes (Russian), 
Izd. Akad. Nauk, Moskau, U.S.S.R., 1949, 830 pp.), and it is developed still 
further in the present edition of the Manual. 

Of the three names used for the different classes of Protophyta, Schizomycetes 
was suggested by von Naegeli (Bericht iiber der Verhandlungen der bot. Section 
der 33 Versammlung deutscher Naturforscher und Xrzter. Bot. Ztng., 15, 1857, 
760) and Schizophyceae by Cohn (Jahresber. Schles. Ges. f . vaterl. Cultur f. 1879, 
279-289), and these have been generally used. The development of our knowledge 
of the rickettsias and viruses is so recent that no truly satisfactory class name 



10 CONSIDERATIONS INFLUENCING CLASSIFICATION 

has previously been suggested for this entire group. This has caused Dr. C. B. 
Phihp, who has acted as editor of the section covering rickettsias and related 
species in the present (7th) edition of the Manual, to suggest the name Microta- 
tobiotes for Class III. The latter is a more appropriate name for the entire group 
of organisms included in the orders Rickettsiales and Virales than any that has 
previously been suggested. Dr. Philip has discussed the new developments in the 
classification of the order Rickettsiales in a recent paper (Canadian Jour. Micro- 
biol., 2, 1956, 261). Therefore the present discussion is limited to an explanation 
of the reasons for increasing the number of orders recognized in Class II, Schizo- 
mycetes von Naegeli, from five to ten. 

The organisms placed in Class II, Schizomycetes von Naegeli, in the 6th edition 
were arranged in five orders as follows: 

Division I. Schizophyta Cohn, 1875. (Fission plants.) 

Class I. Schizophyceae Cohn, 1879. (Fission algae. Blue-green algae.) 
Class II. Schizomycetes von Naegeli, 1857. (Fission fungi, bacteria.) 
Order I. Eubacteriales Buchanan, 1917 (The true bacteria.) 
Order II. Aciinomycetales Buchanan, 1917. (The mycobacteria, actinomyces, 

streptomyces and related forms.) 
Order III. Chlamydohacteriales Buchanan, 1917. (The alga-like, filamentous 

bacteria.) 
Order IV. Myxobacteriales Jahn, 1911. (The slime bacteria.) 
Order V. Spirochaetales Buchanan, 1918. (The spirochetes and related forms.) 

Supplements: Groups whose relationships were regarded as uncertain. 

Group I. Order Rickettsiales Buchanan and Buchanan, 1938, emend. Gieszczy- 

kiewicz, 1939. (Rickettsias and related organisms.) 
Group II. Order Virales Breed, Murray and Hitchens, 1944. (Filterable viruses.) 
Group III. Family Borrelomycetaceae Turner, 1935. (Pleuro-pneumonia-like organ- 
isms.) 

This outline as given above is similar to the outline followed in earlier editions 
of the Manual and is based upon the outline classification developed by Bu- 
chanan (op. cit.) in 1916-18. It is expanded in the present edition of the Manual 
as follows : 

Division I. Protophyta Sachs, 1874, emend. Krassilnikov, 1949.* (Primitive plants.) 
Class I. Schizophyceae Cohn, 1879. (Blue-green algae.) 
Class II. Schizomycetes von Naegeli, 1857. (Bacteria and related forms.) 

Order I. Pseudomonadales Orla- Jensen, 1921. 

Order II. Chlamydohacteriales Buchanan, 1917. 

Order III. Hyphomicrobiales Douglas, 1956. 

Order IV. Eubacteriales Buchanan, 1917. 

* Protophyta was previously used by Endlicher, S. (Genera Plantarum, Vindobonae, 
1836, p. 1) in two different senses: (1) for Sectio I, Algae and Lichens of his Regio I Thal- 
lophyta, (2) for Cohors II of his Sectio III, Acrobrya, to include horse tails, ferns, etc. This 
use may be disregarded under Article 26 of the International Code of Botanical Nomen- 
clature. This reads: "The rules of priority and typification do not apply to names of taxa 
above the rank of orders.". 



CONSIDERATIONS INFLUENCING CLASSIFICATION 11 

Order V. Actinomycetales Buchanan, 1917. 

Order VI. Caryophanales Peshkoff, 1940. 

Order VII. Beggiatoales Buchanan, 1956. 

Order VIII. Myxobacterales Jahn, 1911. 

Order IX. Spirochaetales Buchanan, 1918. 

Order X. Myco-phismatales Freundt, 1955. 
Class III. Microtatobiotes Philip, 1955. 

Order I. Rickettsiales Buchanan and Buchanan, 1938, emend. Gieszczy- 
kiewicz, 1939. 

Order II. Virales Breed, Murray and Hitchens, 1944. 
Division II. Thallophyia Endlicher, 1836. 
Division III. Bryophyta Haeckel, 1866. 
Division IV. Pteridophyta Haeckel, 1866. 
Division V. Spermatophyta Goebel, 1882.* 

It has been felt desirable to subdivide the Order Eubacteriales, as defined in 
the 6th edition of the Manual, into Order I, Pseudomonadales, which includes 
all of the polar-flagellate types of true bacteria, and Order IV, Eubacteriales, 
which includes the peritrichous types of true bacteria. As in the 6th edition, the 
photosynthetic purple and green bacteria that are polar flagellate have been 
included in the order with the colorless polar-flagellate bacteria. This arrangement 
emphasizes a concept first introduced into the classification of bacteria by Migula 
(Arb. Bact. Inst. Karlsruhe, 1, 1894, 235-238). This concept is analogous to the 
concept used by protozoologists who recognize the orders Flagellata and Infusoria 
in Protozoa. 

Bacteriologists have recognized differences between polar flagellate and 
peritrichous bacteria ever since Migula emphasized them, but there has always 
been a residual protest against drawing a sharp line between the two groups of 
bacteria. While there is good reason to draw a sharp line between the ordinary 
polar flagellate types of bacteria and the peritrichous types, there are certain 
groups such as legume nodule bacteria {Rhizobium) , the violet bacteria {Chromo- 
bacterium), the agrobacteria (Agrobacterium) and certain motile forms placed in 
the family Corynebacteriaceae that present a type of peritrichous flagellation that, 
when studied superficially, is misleading. Some cultures of these organisms are 
found to show only a single flagellum, while others closely related to these 
monotrichous species show several flagella peritrichously arranged. On casual 
examination these conditions appear to form a transition between the two types 
of flagellation. However, this clearly is not the case. This apparently intermediate 
type of flagellation seems to be a comparatively recent development in which 
the flagella of certain peritrichously flagellated species have undergone a retro- 
gressive specialization. In this the organisms have become primarily dependent 
on one flagellum as their chief organ of locomotion. They therefore are included 
in Order IV, Eubacteriales, with other peritrichous bacteria. 

* Goebel, K., in his edition of Sach's Grundziige der Systematik und speciellen Pflanzen- 
morphologie, p. 334, 1882, was apparently the first author to use this name, although he 
used the incorrect spelling Spermaphyta. 



12 CONSIDERATIONS INFLUENCING CLASSIFICATION 

Eubacteriales is defined to include not only the bacteria that are peritrichously 
flagellated but also such non-motile forms as seem by their physiology to be 
closely related to these peritrichous species. 

The placing of non-motile species of bacteria in systems of classification has 
always caused difficulty. Some students think that lack of motility is a character 
which should be used as a basis for separation of groups. However, evidence is 
continually accumulating that indicates that separation of larger groups among 
the bacteria solely by means of motility or lack of motility leads to a violent 
disarrangement of natural groupings. Some non-motile bacteria present funda- 
mental physiologies and other characters that show that they are much like 
certain polar flagellate organisms. Such non-motile species are placed in the 
classification used here in Order I, Pseudomonadales. However, where non-motile 
species show fundamental physiologies and other characters more like those of 
peritrichous species, then they have been placed in Order IV, Eubacteriales. 
Organisms living in habitats where they are unable to use organs of locomotion 
are usually found to be non-motile. This is very natural from the standpoint of 
evolution. 

Some bacteria develop into trichomes, which may be defined as chains (fila- 
ments) of bacteria where the relationship between the cells in the chain have 
become so intimate that the cells rarely live a separate, independent existence. 
Sometimes the cells in the chain show a differentiation into hold-fast cells and/or 
reproductive cells distinct from the usual vegetative cells. This differentiation 
resembles that found among the simpler algae. Because the cells in these tri- 
chomes sometimes develop flagella that are placed singly or in a tuft near or at 
the pole of the cell, while others develop cells with peritrichous flagella, it has been 
felt desirable to recognize two orders among these bacteria that occur in tri- 
chomes: Order II, Chlamydobaderiales, for the polar flagellate types and Order VI, 
Caryophanales, for the peritrichous types. Some non-motile species occur in these 
orders also. 

Little is known about the relationships of certain species of bacteria which 
show a budding form of reproduction that is different from the simple cell division 
(fission) that takes place in the four orders previously discussed. Only a few of 
these species that reproduce by budding are well known, though some of them 
occur abundantly in suitable habitats. Because the indications are that many 
species of these organisms exist in nature. Prof. H. C. Douglas has set these apart 
in a new order, Hijphomicrohiales, p. 276. Where flagellation has been observed 
among these budding forms, it is of the polar type so that Order III has been 
associated with Order I, Pseudomonadales, and Order II, Chlamydohacteriales, 
in the arrangement of the 10 orders as given above. 

Until recently everyone has thought of Order V, Actinomycetalcs, as including 
species all of which were non-motile.* However Couch, in a series of papers, 
the latest published in 1955 (Jour. Elisha Mitchell Sci. Soc, 71, 1955, 148-155), 

* Also see footnote p. 713 for a discussion of motility in species of Nocardia by H. L. 
Jensen. 



CONSIDERATIONS INFLUENCING CLASSIFICATION 13 

has shown that microorganisms that belong in this order sometimes exist in 
water rather than as pathogens affecting animals or plants or in soil. These 
water-inhabiting, saprophytic types of Actinomycetes have developed sporangia 
in which motile or non-motile spores may develop. In a way they are analogous 
to the so-called water molds. The structure of the vegetative cells and mycelia 
of these water-inhabiting Actinomycetes is like that of the aerobic Actinomycetes. 

Order VII, Beggiatoales, has been organized by Dr. R. E. Buchanan, page 837, 
to include a group of bacteria, primarily ocurring in trichomes, that are motile 
but which lack flagella. In spite of this lack they have the power to glide, roll or 
oscillate as do certain species of blue-green algae. While none of these bacterial 
types develop photosynthetic pigments, they are frequently and apparently 
quite properly regarded as colorless, saprophytic forms of blue-green algae. 
Certain species oxidize sulfur compounds with the liberation of free sulfur gran- 
ules. Some specialists prefer to transfer this group to Class I, Schizophyceae, as 
colorless species of blue-green algae rather than to include them with Class II, 
Sch.izomycetes. As bacteriologists have been primarily responsible for developing 
our knowledge of the species in this order, they are retained here in Class II, 
Schizomycetes. 

Our knowledge of Order VIII, Myxobacterales, the so-called slime bacteria, 
was first developed by botanists rather than bacteriologists. These organisms 
occur in leaf mold and on the dung of animals. Recently species causing diseases 
of fish have been found. The cells of these species move with a flexuous motion 
in a slime which normally grows up into fruiting bodies large enough to be visible 
to the naked eye. 

The organisms placed in Order IX, Spirochaetales, have always been set off 
by themselves though certain species are knoA\Ti that are so much like other 
species of bacteria placed in the genus Spirillum in Order I, Pseudomonadales, 
that they may be regarded as transitional forms. Sometimes, without sufficient 
justification, these spirally twisted organisms have been placed among the 
Protozoa. 

The tenth order of Class II, Schizomycetes, is the newly organized Order X, 
Mycoplasmatales Freundt. Because a review of the nomenclature of the pleuro- 
pneumonia-like organisms (Buchanan, Cowan and Wiken, Internat. Bull. Bact. 
Nomen. and Taxon., d, 1955, 13-20) has shown that the first generic name applied 
to these organisms that has a legitimate standing is M mycoplasma Nowak (Ann. 
Inst. Past., 43, 1929, 1330-1352), this name has been adopted for use in the 
classification of the pleuropneumonia-like organisms that has been prepared 
by Freundt (Internat. Bull. Bact. Nomen. and Taxon., 6, 1955, 67-78). This 
generic name has also been used by Edward (Internat. Bull. Bact. Nomen. and 
Taxon., 5, 1955, 85-93). While other order names, such as Borrelomycetales 
Turner (Jour. Path, and Bact., 41, 1935, 1-32), have been suggested, the generic 
name Borrelomyces Turner on which the order name is founded has never come 
into general use, and Borrelomyces is in fact an illegitimate homonym of Myco- 
plasma Nowak. Acceptance of the order name Mycoplasmatales is in accordance 



14 CONSIDERATIONS INFLUENCING CLASSIFICATION 

with the principles of the Bacteriological Code of Nomenclature, and it should 
tend to stabilize the nomenclature of this group. 

In closing this discussion of the revised classification, it should again be em- 
phasized that it has been developed as a result of a study of the ideas which 
previous workers have expressed in preparing the outlines that they have sug- 
gested. Previous workers have laid what appears, with our present knowledge, 
to be a satisfactory foundation on which to build. The introduction of new ideas 
has come about largely as a result of continuous study of the literature and 
conferences with our colleagues, including the specialists who have contributed 
and are contributing so much to the knowledge that has accumulated in past 
years. A generous share of the credit for the things that constitute a real advance 
in our knowledge should go to these specialists. Where the classification here 
presented has defects, it is to be hoped that they will be discovered promptly 
and eliminated. 



HOW BACTERIA ARE NAMED AND IDENTIFIED 

Prof. R. E. Buchanan 

Dean of Graduate School {Emeritus) atid Director of Experiment Station (Emeritus), 
Iowa State College, Ames, Iowa 

A manual of determinative bacteriology, such as the present volume, has 
several important functions. These should be recognized and understood by the 
student if he is to use the volume with satisfaction. 

First, the manual should list and describe all the kinds (species) of bacteria 
and viruses known through adequate publication in bacteriology or virology. 
Obviously, however, only those organisms that have usable published descrip- 
tions can be included. 

Second, the manual should arrange the descriptions of the kinds (species) in 
smaller or larger groups (taxa, singular, taxon) on the basis of resemblances and 
differences in an effort to show inter-relationships. 

Third, the manual should indicate for each species its correct name, likewise 
the correct name for each group (taxon) of related species. 

That branch of biology which has for its purpose the orderly arrangement of 
the descriptions of species and other taxa, together with the application of the 
correct names, is termed taxonomy. 

The manual, through its indices, should enable the student who knows the 
correct name of an organism (or even a synonym of such name) to discover the 
description of the organism and its characteristics, as well as something of its 
relationships. If, on the other hand, he has an organism whose characteristics 
and description he has determined or recorded, but whose name and relation- 
ships he does not know, a satisfactory manual, through its keys, should enable 
him to determine the correct name, its probable relationships and its position in 
a classification. 

Nomenclature. The necessity for applying names to species or kinds of bacteria 
and to groups of inter-related organisms is self-evident. A name given by one 
person should be understood by others, and as far as practicable all individuals 
should use the same name for the same kind of organism. It is helpful, therefore, 
if there can be agreement regarding the method of naming bacteria and agree- 
ment as to the correct name for each kind or species. Nomenclature includes all 
discussions as to methods of naming and of the correctness of particular names. 

What kinds of names are used. Two kinds of names are commonly given 
to the different species of plants and animals, (1) the common, provincial, ver- 
nacular or casual names and (2), the international or scientific names. These 
should be carefully differentiated, and their respective advantages and disad- 
vantages noted. 

It is inevitable, and on the whole probably desirable, that for each kind of 

15 



16 HOW BACTERIA ARE NAMED AND IDENTIFIED 

familiar animal or plant in each language there will be coined a name. Usually 
the name for the same organism will be different in each language. For example, 
we have in English Oak, in German Eiche, in Latin Quercus, etc. For many less 
common kinds, however, there may be no such vernacular names developed. 
There have been, of course, many casual or vernacular names given to kinds of 
bacteria. In English Ave speak of the tubercle bacillus, the typhoid germ, the 
gonococcus, the Welch bacillus, the golden pus coccus, and many others. Simi- 
larly, we find in German Typhusbazillus and in French bacille typhique, entero- 
coque, etc. Not infrequently scientific names may be adopted into a modern 
language and converted into vernacular names. For example, the English name 
aster and the scientific generic name Aster are applied to the same group. This 
is freciuently a convenience, and in general this practice is to be commended. 
For example, many of the "scientific" generic names used in bacteriology are 
also used as names in English and other languages. This adaptation is particu- 
larly convenient when the organisms in the group under discussion are of im- 
portance and are frequently referred to in the literature. Custom and nomen- 
clatural rules suggest certain discretion and appropriateness in the use of these 
casual or vernacular names. The following suggestions, based upon nomenclatural 
precedent and custom, should prove useful to the student. 

1. The name of a genus is a noun in the singular. It is not a collective noun 
and should never be used with a plural verb. Do not use such an expression as 
"The Salmonella are abundant." 

2. However, custom since the beginning of binomial nomenclature has sanc- 
tioned the use of the plural of generic names. One may say "The Sahnonellae 
(Corynehacteria, Rhizohia, Sarcinae, Bacilli) are." These Latin plurals are used 
with the meaning "The species of the genus Salmonella (etc.) are." They do not 
connote the existence of more than one genus Salmonella. 

3. Custom has also sanctioned the use of the generic name in the singular in 
an expression such as "This Sarcina is yellow" with the meaning "This species 
of Sarcina is j^ellow." 

4. The Latin plural of a generic name should be employed whenever the name 
is used as indicated in 2 above. "The Salmonellas or Sarcinas are ..." should be 
avoided because of the use of the English plural endings. 

5. An English (vernacular) name may be coined from any generic name. This 
is done usually only for genera that are under length}^ discussion or of consider- 
able economic significance. 

6. An English, or vernacular, name of a genus may be used also in the plural, 
as in "the corynehacteria are . . ." with the meaning "The species of coryne- 
bacterium under consideration." When a Latin generic name is converted into 
the English vernacular, either the English or the Latin plural may be used. 
Perhaps the Latin plural is the better choice, but one finds "The salmonellas 
are ... ." Note that when used as a vernacular (English) word the generic name 
is never regarded as a proper noun and is not capitalized or italicized. 

More than one form of a name may be derived in English (vernacular) from a 



HOW BACTERIA ARE NAMED AND IDENTIFIED 17 

generic name. A member of the genus Spironema may be termed a spironema 
or a spironeme, a member of the genus Sireptomyces a streptomyces or a strepto- 
mycete. 

7. A genus includes usually se\eral to many species; it is the name of a group 
of species. The expression "The genus Salmonella is . . ." or ''Salmonella is . . ." 
should always be preferred to such ambiguous phrases as "The Salmonella 
^roup is." 

In contrast to common, vernacular or casual names, the scientific name for 
each kind of organism is planned to be the same in all countries and in all lan- 
guages. When a correct scientific name is used, no question should arise in any 
language as to what organism is intended. The names thus applied are supposed 
to conform to certain general rules. 

International codes of nomenclature. In order that there be correct 
scientific names, it is essential that there be international agreement as to the 
rules governing their creation. Botanists and zoologists have met in numerous 
international congresses in which delegates were accredited from the great 
botanical and zoological societies, museums and educational institutions of the 
world. Codes of nomenclature, designed to tell how names of taxa should be 
published and to list the criteria of correctness, have been developed. These 
codes or lists of rules and recommendations are quite similar in essentials for 
botany and zoology, although they differ in some details. 

The question arose in bacteriology: Are either or both of these codes satis- 
factory or adaptable to the use of microbiologists? Three views have been ex- 
pressed by various writers. Some few suggested that the naming of bacteria 
cannot well conform to the approved international rules as their classification 
involves considerations not familiar to botanists and zoologists generally. The 
second group insisted that unicellular forms of life are neither plants nor animals, 
but Protista, and that taxonomic rules, etc., should be distinct for this group 
and coordinate with the corresponding rules for plants and for animals. The third 
view, more commonly expressed, was that the bacteria are sufficiently closely 
related to the plants and animals so that (in so far as they apply) the interna- 
tional agreements of the botanists (or zoologists) should be used as a basis for 
naming them. 

International opinion on this topic was finally crystallized by resolutions 
adopted by the First International Congress of the International Society for 
Microbiology held in Paris in 1930. These resolutions, approved also by the ple- 
nary session of the International Society for Microbiology, were in part as fol- 
lows : 

"It is clearly recognized that the living forms with which the microbiologists 
concern themselves are in part plants, in part animals, and in part primitive. It 
is further recognized that in so far as they may he applicable and appropriate the 
nomenclatural codes agreed upon by International Congresses of Botany and 
Zoology should be followed in the naming of micro-organisms. Bearing in mind, 
however, the peculiarly independent course of development that bacteriology 



18 HOW BACTERIA ARE NAMED AND IDENTIFIED 

has taken in the past fifty years, and the elaboration of special descriptive cri- 
teria which bacteriologists have of necessity developed, it is the opinion of the 
International Society for Microbiology that the bacteria constitute a group for 
which special arrangements are necessary. Therefore the International Society 
for Microbiology has decided to consider the subject of bacterial nomenclature 
as a part of its permanent program." 

The International Society established a permanent Nomenclature Committee 
to pass upon suggestions and to make recommendations. This committee is 
composed of members (about 100 in all) from the participating nations. Two 
permanent secretaries were named, one to represent primarily medical and 
veterinary bacteriology, and one to represent other phases of bacteriology.* 

It soon became apparent that the botanical and zoological codes of nomen- 
clature included many items having no significance in bacteriology and virology 
and that bacterial and viral nomenclature required special consideration. 

In 1936, at the London International Microbiological Congress, it was decided 
that an independent, but closely integrated. Code of Bacteriological Nomen- 
clature be developed. In 1939, at the next International Congress, a Judicial 
Commission of fourteen was appointed and directed to prepare a code for con- 
sideration at the next Congress. The International Code of Bacteriological 
Nomenclature prepared by the Commission was approved in 1947 by the Inter- 
national Committee and by the plenary session of the Copenhagen Congress. 
These rules were published in English in March, 1948, f and later in French, 
Spanish, German and Japanese. 

The Code was amended at Rio de Janeiro in 1950 and at Rome in 1953. The 
present code should be accessible to all bacteriologists and virologists. It has 
been edited and annotated by the Editorial Board of the Judicial Commission.} 
It should be consulted by all who wish to determine the correctness of names used 
in the literature and by those who describe new species or other taxa. 

Some general principles of nomenclature. Every student of bacteriology 
should be familiar with certain rules of nomenclature if he is to use names in- 
telligently. If he wishes to correct names improperly used or if he desires to 
name new species, some additional rules should be observed: 

1. Each distinct kind of bacterium is called a species. 

2. To each distinct species a name is given consisting usually of two Latin 
words, as Bacillus suhtilis. 

3. The first word is the name of the genus or group to which the organism 
belongs. It is always written with a capital letter. It is a Latin or latinized Greek 

* The permanent secretary for medical and veterinary bacteriology at the present time 
is Dr. S. T. Cowan, National Collection of Type Cultures, Central Public Health Labora- 
tory, Colindale Avenue, London, N.W. 9, England. The permanent secretary for general 
bacteriology at the present time is Dr. T. Wiken, Laboratory for Microbiology, Technical 
University, Delft, Holland. 

t International Bacteriological Code of Nomenclature. Edited by R. E. Buchanan, 
R. St. John-Brooks and R. S. Breed. Jour. Bact., 55, 1948, 287-306. 

t In press, 1956. 



HOW BACTERIA ARE NAMED AND IDENTIFIED 



19 



word, or a new word compounded from Latin or Greek stems, or it may be de- 
rived from some other language; but whatever its origin, when used as a generic 
name, it must he regarded as a Latin noun. If it is a word not found in classic 
Latin, it is still to be treated as Latin. Some examples of generic names in bac- 
teriology which are Latin or which are formed from Latin roots are: Bacillus 
(masculine) a small rod; Cristispira (feminine) a crested spiral; Lactobacillus 
(masculine) a milk small rod; Sarcina (feminine) a packet or bundle. Many 
others are words from the Greek or are compounded from Greek roots, the words 
transliterated into Latin letters and with endings modified in conformity with 
Latin usage; some words of Greek origin are Micrococcus (masculine) a small 
grain (sphere); Bacterium (neuter) a small rod; Clostridium (neuter) a small 
spindle; Corijnebacterium (neuter) clubbed small rod; Actinomyces (masculine) 
ray fungus. Other generic names have been given in honor of persons or places as 
Beggiatoa (feminine), Borrelia (feminine), Eherthella (feminine), Pasteurella 
(feminine), Erwinia (feminine), Zopfius (masculine). 

4. The second word in the scientific name of a species is a specific epithet. It 
is not capitalized (some authors capitalize species names derived from proper 
nouns). The specific epithet may be: 

(a) An adjective modifying the noun and indicating by its ending agreement 
with the generic name in gender, as Bacterium album (white Bacterium), Bacillus 
albus (white Bacillus), Sarcina alba (white Sarcina), Eberthella dispar (different 
Eberthella), Bacterium variabile (variable Bacterium) , Brucella melitensis (maltese 
Brucella), Bacillus teres (rounded Bacillus), Bacillus graveolens (sweet-smelling 
Bacillus). 





Typical adjectives 






Masculine 


Feminine 


Neuter 


white 


albus 


alba 


album 


black 


niger 


nigra 


nigrum 


delicate 


tener 


tenera 


tenerum 


sharp 


acer 


acris 


acre 


variable 


variabilis 


variabilis 


variabile 


different 


dispar 


dispar 


dispar 


Uke a berry 


coccoides 


coccoides 


coccoides 


gas-forming 


aerogenes 


aerogenes 


aerogenes 



(b) An adjective in the form of the present participle of a verb, as Clostridium 
dissolvens (the dissolving Clostridium, in the sense of the Clostridium which is 
able to dissolve). Bacillus adhaerens (the adhering Bacillus), Acetobacter ascen- 
dens (the climbing Acetobacter), Bacillus esterifix^ans (the ester-producing Bacil- 
lus). The endings for present participles used as adjectives are the same for all 
genders. The past participle is used occasionally, as in Pseudomonas aptata (the 
adapted Pseudomonas), Spirillum attenuatum (the attenuated Spirillum). 

(c) A noun in the genitive (possessive) modifying the generic name. There is 
no necessary agreement in gender or number. Examples, Clostridium welchii 



20 HOW BACTERIA ARE NAMED AND IDENTIFIED 

(Welch's Clostridium), Salmonella pullorum (the Salmonella of chicks), Strepto- 
coccus lactis {the Streptococcus of milk), Brucella abortus (the Brucella of abortion), 
Clostridium tetani (the Clostridium of tetanus), Diplococcus pneumoniae (the 
Diplococcus of pneumonia), Salmonella anatum (the Salmonella of ducks). 

(d) A noun in apposition, that is, an explanatory noun. This does not agree 
necessarily with the generic name in gender. This method of naming is relatively 
uncommon in bacteriology. Examples are Actinomyces scabies (the scurf or scab 
Actinomyces) , Bacillus lacticola (the milk-dweller Bacillus), Rhizobium radicicola 
(the root-dweller Rhizobium), Salmonella london (The London Salmonella). 

5. The author of the name of a taxon is often cited by having his name follow 
that of the species, as Bacillus subtilis Cohn. Sometimes the name of another 
author is indicated also in parentheses, as Micrococcus luteus (Schroeter) Cohn. 
This means that Schroeter first named the species, giving it the specific epithet 
luteum, (placing it in the genus Bacteridium) . Cohn transferred it to the genus 
Micrococcus. It should be noted that the name of a person following that of an 
organism frequently is not that of the individual who first discovered or described 
it, but of the person who first gave it the accepted name. For example, Clostrid- 
ium welchii (Migula) Holland was first described by Dr. Wm. H. Welch, but 
not named by him. It was named by Migula in honor of Dr. Welch and later 
placed in the genus Clostridium by Holland. 

6. Sometimes species of bacteria are subdivided into subspecies or varieties. 
These are likewise given Latin designations, and the entire name written, as: 
Streptococcus lactis subspecies (var.) maltigenes (the Streptococcus of milk produc- 
ing malt flavor), or merely Streptococcus lactis maltigenes. 

Some principles of taxonomy. The student of bacteriolog}^ should recognize 
the meaning of certain terms used regularly in classifications. 

(1) Species (plural species). A species of plant (or animal) is assumed above 
to be one kind of plant. But how much difference must exist between two cul- 
tures of bacteria before one is justified in regarding the organisms in them as 
being of distinct kinds or species? No rule can be laid down. It depends largely 
upon convenience and upon more or less arbitrary but considered decision. As 
stated by Hitchcock (Descriptive Systematic Botany, New York, 1925, p. 8): 
"The unit of classification is a coherent group of like individuals, called a species. 
The term is difficult to define with precision because a species is not a definite 
entity, but a taxonomic concept." Hucker and Pederson (New York Agric. 
Exper. Sta. Tech. Bull. 167, 1930, p. 39) state: "The difficulty met with among 
these lower forms in dividing them into well-defined groups has led many to 
question whether these small groups of 'species' are natural groups and whether 
such groups can be considered to be similar to 'species' among higher forms. 
However this may be, it is necessary to arrange bacteria as well as possible into 
groups or so-called 'species' for convenience in classification," and again (Hucker, 
New York Agric. Exper. Sta. Tech. Bull. 100, 1924, p. 29), "characters appli- 
cable to the differentiation of species must evidence a certain amount of con- 
stancy when studied over a large series of tests. Furthermore, characters adapted 



HOW BACTERIA ARE NAMED AND IDENTIFIED 21 

to the differentiation of larger natural groups or genera should, in addition to 
constancy, show some correlation with other constant characteristics. The pres- 
ence of this relationship or correlation between characters for the division of 
genera indicates that the groupings are being made along natural rather than 
artificial lines." 

Type culture. It is quite evident that when a new species of bacterium is de- 
scribed, it must include the particular culture from which the species description 
was made. This original culture is termed the type culture. One may develop a 
definition as follows: A species of bacterium is the type culture or specimen 
together with all other cultures or specimens regarded by an investigator as 
sufficiently like the type (or sufficiently closely related to it) to be grouped with 
it. It is self-evident that different investigators may not draw the same bound- 
aries for a given species. There are some practical difficulties, but no better 
definition has been evolved. 

(2) Genus (plural genera). A genus is a group of related species. In some 
cases a genus may include only a single species (is said to be monotypic); in 
most cases several to many species are included in a genus. The ciuite pertinent 
ciuestion should be asked: How close must be the resemblances (how close the 
relationships) among the species of a group to entitle them to inclusion in the 
same genus? In other words, how is it possible to delimit accurately the bound- 
aries of a genus? This is a matter on which there is no agreement, and probably 
can be none. Much of the confusion in modern bacteriological terminology is to 
be attributed to this fact. Nevertheless, in the course of time experience tends to 
delimit many genera with reasonable accuracy. As stated by Hitchcock (De- 
scriptive Systematic Botany, New York, 1925, p. 9): "Convenience may play 
a role in determining generic lines. Extremely large groups may be broken up 
on the basis of differences of smaller degree not common to a group of closely 
allied species, than if the group consisted of a few species. In general, the botanist, 
in delimiting genera, keeps in mind two important rec^uirements, that of showing 
natural aflftnities and that of aiding correct identification." 

However, a genus may be defined helpfully in another way. One of the species 
described as belonging to a genus is designated as the type species; a genus may 
therefore be defined as including this type species together with such other 
species as the investigator (or taxonomist) regards as sufficiently closely related. 
It is apparent that some authors may draw the lines narrowly, others broadly. 
Some early authors, for example, recognize only two genera of rod-shaped bac- 
teria, one for those without endospores {Bacterium), and one for those producing 
endospores {Bacillus). These genera thus defined are very large, each containing 
hundreds, perhaps thousands, of species. Other students break up these large 
genera into many smaller ones. There is not much point to the question as to 
which is right and which is wrong. A better question is, which is the more con- 
venient, better represents relationships, better facilitates diagnosis, and proves 
most useful. 

(3) Family. A family in taxonomy is a group of related genera one of which 



22 HOW BACTERIA ARE NAMED AND IDENTIFIED 

is designated as the type genus. In general the name of the family is formed from 
the name of the type genus by affixing the suffix -aceac to the stem of the generic 
name. The word is plural. Among bacterial families commonly recognized are 
Bacillaceae, named from its type genus, Bacillus^ Pseudomonadaceae from Pseu- 
domonas, Spirochaetaceae from Spirochaeia, Actinomycetaceae from Actinomyces 
and Spirillaceae from Spirillum. 

(4) Order. An order is a group of related families. It is usually named by 
substituting the suffix -ales for -aceae in the name of the type family. Among 
ordinal names that have been used in bacteriology are Actinomijcetales, Spiro- 
chaetales, Myxohacterales. 

(5) Class. A class is a group of related orders. In this treatise the bacteria 
are treated as constituting the class Schizomycetes in Division I., Protophyta, of 
the plant kingdom. 

(6) Other categories. Other categories or ranks of names are used for higher 
groups. Sometimes families are divided into sub-families, these into tribes, these 
into subtribes, and these finally into genera. 

How to identify an organism by name. One of the purposes of this Man- 
ual OF Determinative Bacteriology, as noted previously, is to facilitate the 
finding of the correct scientific name of a bacterium. It is well, however, to note 
some of the reasons why this result, the identification of an unknown culture, 
may not eventuate. Among these the following may be listed: 

(1) The unknown organism awaiting identification b}^ the investigator may 
possibly be one which has never been named; or, if named, perhaps was inade- 
quately described. Of course it will not be listed in the Manual. Little effort 
on the part of bacteriologists has been devoted to describing or naming bacteria 
except as they have been found to have some economic significance or to possess 
some striking or unusual characteristics. There are quite probably many times 
as many species of unknown bacteria as have been described and named. Such 
unknown species are all about us. It is not surprising, therefore, if one some- 
times encounters undescribed species. When such unnamed species are found, 
particularly if they are of economic importance or are related to such forms, it 
is highly desirable that they should be adequately described and named, and 
the results published and made accessible. 

(2) The unknown organism may have been described and named in some 
publication, but the description and name have been overlooked in the prepara- 
tion of the Manual. Perhaps the description has been so inadequate or incom- 
plete that it has not been possible to place it in a satisfactory classification. It 
should be noted that the number of species that have been described is so great 
that no one individual can know them all. Progress in classification comes about 
largely as the result of the work of specialists in particular groups. Unfortunately 
most groups of bacteria have not been adequately monographed. It is evidently 
the function of a Manual such as this to draw largely upon the work of those 
who have published monographs covering special groups of bacteria and to 
supplement their achievements as far as possible by a necessarily less satisfactory 
consideration of the unmonographed groups. It is clear that the fact that an 



HOW BACTERIA ARE NAMED AND IDENTIFIED 23 

organism cannot be identified from this text is no proof that it has not been 
described and named. 

(3) It is possible, of course, that an error has been made in the selection of 
the correct name in this Manual. Bacteriological literature has, in recent years, 
been engaged in the herculean task of rectifying the nomenclatural blunders of 
the past. It is desirable, therefore, that users of the keys and descriptions of this 
Manual should be familiar with the rules governing the correct choice of names, 
and themselves propose suitable corrections where needed. 

Some general rules governing nonienelature that should be known to 
students of bacteriology. In summary, some of the more important rules and 
recommendations of the Bacteriological Code may be briefly paraphrased. In 
case of doubt, the Annotated Code itself should be consulted. 

1. Every individual microorganism belongs to a species, every species to a 
genus, every genus to a family, every family to an order, every order to a class. 
Each one of these ranks is called a taxon (plural taxa) (Principle 7). 

2. Each taxonomic group (taxon) with a given definition (circumscription), 
position, and rank can bear only one correct name, the earliest name given to it 
that is in accordance with the rules of nomenclature (Principle 9) . 

3. The name of a species is made up of two words consisting of the name of 
the genus followed by the specific epithet. The term "epithet" means a single 
descriptive word or a single descriptive phrase. If the latter, the component 
words are to be united or joined by a hyphen. Within the same genus, no two 
species names may bear the same specific epithet (Rule 6). 

4. Each taxon (species, genus, family, order) should have designated a nomen- 
clatural type. The type of a bacterial species is preferably a designated culture 
preferably maintained in a national type culture collection. When a new species 
is described and named, a culture should be deposited by the author with such 
type culture collection where it will be available as a standard and useful in 
identification of other cultures believed to be related. 

The nomenclatural type of a genus is a species of the genus selected in accord- 
ance with the rules. 

The nomenclatural type of a family is a genus contained within the family. 
The family name is formed by adding the ending -aceae to the stem of the name 
of the type genus. The nomenclatural type of the family Pseudomonadaceae is 
the genus Pseudomonas (Rule 9). 

5. Correct names. For the name of a taxon (species, genus, family, etc.) to 
be correct it must meet certain requirements. The most important of these are 
as follows : 

a. The name must be the oldest that conforms to the rules. 

b. The name must have been validly published. This means that the name 
must have been distributed in printed matter (periodicals, books, other 
publications) together with a description or clear reference to a previously 
published description. The name must be accepted by the author. It is not 
validly published if merely cited as a synonym. A name that has not been 
validly published is without standing in nomenclature. 



24 HOW BACTERIA ARE NAMED AND IDENTIFIED 

c. A legitimate name is one that conforms to all the nomenelatural rules. 

d. A correct name of a taxon is that legitimate name which for a given taxon 
takes into consideration the boundaries or circumscription of the taxon. 
For example, if one author recognizes two species in a genus, each species 
will have a correct name determined by the application of the rules. An- 
other author may unite the two into a single species, which will have a 
correct name under the rules. 

6. Citation of authors and names. 

a. It is customary in formal use of the name of a species to cite the name of 
the author, usually with the year of publication. This means exactly what 
it says, one cites the author of the name of the taxon being used. This is 
not necessarily the name of the author who first described the organism. 
For example, one cites Bacillus suhtilis Cohn, 1872. 

b. When a named species is transferred to another genus, the name of the 
author who proposed the specific epithet is inserted in parentheses between 
the new species name and the name of the author of the new combination. 
For example, Neisser and Kuschbert in 1883 named an organism Bacillus 
xerosis. Lehmann and Neumann in 1899 transferred this organism to their 
newly created genus Corynebacterium, correctly retaining the original 
specific epithet (as xerose to agree in gender with Corynebacterium), and 
the new combination is cited as Corynebacterium xerose (Neisser and 
Kuschbert, 1883) Lehmann and Neumann, 1899. Obviously citation of 
author and date with the name of an organism is necessary only when the 
organism is first mentioned in a publication. 

7. Changes in names required by union or segregation of taxa. 

a. When a genus is divided into two or more genera, the generic name must 
be retained for one of them. The generic name must be retained for the 
genus containing the type species. 

b. When a species is divided into two or more species, the specific epithet 
must be retained for one of them. The specific epithet of the species con- 
taining the type must be retained for this species. 

c. When a species is transferred from one genus to another, the specific 
epithet is retained unless the resulting species name is a later homonym 
or a tautonym or unless there is available an earlier validly published 
specific epithet. 

8. Rejection and replacement of names. 

a. A name or epithet must not be rejected, changed or modified merely be- 
cause it is badly chosen or disagreeable, or because another is preferable 
or better known. Exceptions can be made only by international action 
through the Judicial Commission of the International Committee. 

b. A name must be rejected if it is illegitimate, that is, if it is contrary to a 
rule. There are numerous defects which may make a name illegitimate, 
for example, it may have been superfluous when proposed. Exceptions can 
be made by international approval through action of the Judicial Com- 



HOW BACTERIA ARE NAMED AND IDENTIFIED 25 

9. Spelling and gender of names of taxa. 

a. The original spelling of a name or epithet must be retained, except in the 
case of a typographical error or of a clearly unintentional orthographic 
error. It may be difficult to determine when a typographical or orthographic 
error has occurred. In cases where there is doubt it is advisable to ask the 
Judicial Commission to consider the matter and to render an OPINION 
which ^\all be authoritative. 

b. The gender of generic names is determined as follows: 

(1) A Greek or Latin word adopted as a generic name retains the gender 
of the Greek or Latin. 

(2) Generic names which are modern compounds formed from two or more 
Greek or Latin words take the gender of the last component. If the 
ending is changed from that of the original Greek or Latin word, the 
gender is determined by the rules of gender of the Greek or Latin 
respectively. 

(3) Arbitrarily formed generic names, i.e., those not formed from Latin 
or Greek, take the gender assigned to them by their authors. Where 
the original author did not indicate the gender, the next subsequent 
author has the right of choice. 

10. Provisions for exceptions to the rules or for their interpretation. 
Whenever, in the opinion of any microbiologist, an interpretation of any rule 
or recommendation of nomenclature is desirable because the correct application 
of such rule or recommendation is doubtful, or the stability of nomenclature could 
be increased by the conservation or by the rejection of some name which is a 
source of confusion or error, it is recommended that he prepare a resume out- 
lining the problem, citing pertinent references, and indicating reasons for and 
against specific interpretations. This resume should be submitted to the Chair- 
man of the Judicial Commission; if desired, through one of the Permanent 
Secretaries. An OPINION will be formulated, which may not be issued until 
it has been approved by at least eight members of the Commission. 

Before the preparation of an OPINION, a preliminary statement is usually 
published in the International Bulletin of Bacteriological Nomenclature and 
Taxonomy, the official organ of the International Committee on Bacteriological 
Nomenclature, Iowa State College Press, Ames, Iowa, U. S. A. 

Those who are interested in the solution of special nomenclatural problems 
have open to them as an avenue of communication and publication the columns 
of the International Bulletin. The Board of Editors includes the chairman of the 
Judicial Commission and the two permanent secretaries. Requests for assistance 
in the solution of bacteriological nomenclatural problems may be sent to any 
member of the Editorial Board at the following addresses: 

Prof. R. E. Buchanan, Chairman of Judicial Commission and of the Editorial 
Board. Room 316 Curtiss Hall, Iowa State College, Ames, Iowa, U. S. A. 

Dr. S. T. Cowan, Permanent Secretary of the International Committee and 
of the Judicial Commission. National Collection of Type Cultures, Central 
Public Health Laboratory, Colindale Avenue, London, N.W. 9, England. 



26 HOW BACTERIA ARE NAMED AND IDENTIFIED 

Prof. Dr. Torsten Wiken, Permanent Secretary of the International Commit- 
tee and of the Judicial Commission. Laboratory for Microbiology, Tech- 
nical University, Delft, Holland. 

Derivation, accentuation and pronunciation oj names of taxa and of specific epi- 
thets. A serious attempt has been made in this Manual to give the derivation of 
the words used as names of taxa (genera, families, etc.) and of the specific epi- 
thets of the species names of the microorganisms described. Some guide to pro- 
nunciation is given by designation of the principal accent. The rules clearly state 
that all names of taxa are to be treated as Latin. But in modern times the pro- 
nunciation of Latin words shows little uniformity. However, the principal accent 
can be properly placed. Syllabication of the words may also be helpful. 

L No Latin word consisting of two or more syllables is accented on the last 
syllable. 

2. A Latin word consisting of two or more syllables is accented either on the 
next to the last syllable (the penult) or on the second to the last syllable (ante- 
penult) . 

How may one determine which of the two syllables is to be accented? The rule 
is easily stated. If the next to the last syllable (penult) is long, it should be ac- 
cented; if short, the preceding syllable (antepenult) is to be accented. 

When is a syllable said to be long? There are several criteria; those most readily 
recognized are as follows: 

L If a syllable has a single long vowel, the syllable is long. A standard Latin 
dictionary will indicate whether the vowel is long. In words derived from Greek 
those syllables containing omega (w) or eta (77) are long, those with omicron (o) or 
epsilon (e) are short. In a Greek lexicon the other vowels are usually marked to 
indicate length. 

2. If a syllable contains a diphthong, it is long. 

3. If there is a double consonant or two consonants following a vowel, the 
syllable is long. For example: 

Ba.cil'lus. The accent is on the next to the last syllable (penult) because of the 

double I. 
Bac . te'ri . um. The accent is on the antepenult because the vowel in the penult 

is short. 
Ba.cil.la'ce.ae. The accent is on the antepenult because the vowel of the 

penult is short. 
Spi.ro. ne'ma. The accent is on the penult because the vowel of the penult 

is long; it is the Greek eta (77). 
Micros. pi'ra. The Greek epsilon iota (et) is a diphthong; when translated into 

Latin, it becomes a long i, and the accent is on the penult. 
Use of Greek and Latin in naming taxa. The Greek and Latin alphabets are not 
identical. Greek words to be used as stems for the Latin names of taxa must be 
transliterated into Latin (not translated) ; the Greek letters must be changed to 
the Latin equivalents. The Latins developed well-recognized rules for doing this. 
With most letters the shift is simple, in other cases, the changes are more compli- 



HOW BACTERIA ARE NAMED AND IDENTIFIED 27 

cated. Before a Latin name of a taxon is formed, the Greek word needs to be 
spelled with Latin letters, and the whole word placed, when possible, in the corre- 
sponding Latin declension with appropriate gender ending. How can the Greek 
deri\'ations be indicated without confusion to the student who knows little or 
nothing of Greek? In this Manual the following procedure has been adopted as 
standard and as probably the most readily understood. The student must remem- 
ber that the change is from Greek to Latin (not to English) orthography. The 
system used here is not that usually found in giving derivations in medical or 
general English dictionaries. Some illustrations may be helpful. 

The Greek word for sulfur is delov. The first letter, theta (6), has no Latin equiv- 
alent; the Latins used th. The second letter, epsilon (e), is the equivalent of short 
e in Latin. The third letter, iota (t), is equivalent to i, the fourth, omicron (o), is 
short 0, and the last, nu (v), is n. One may transliterate as theion. But the et of the 
Greek, a diphthong, was transliterated by the Latins as a long i. The ending ov 
of the Greek indicates that the noun is neuter. The corresponding neuter ending 
in Latin is um. In final form we may write deiop = theion = thium. In the Manual 
the statement given is simply Gr. neut. n. (Greek neuter noun) thium sulfur. Thi 
is the stem from which a great number of new Latin names of taxa have been 
constructed, as Thioploca, Thioderma, Thiocystis. 

Some awkward transliterations are to be found in the literature. The Greek 
diphthong at = ai was usually transliterated as ae by the Latins. The Greek 
alfxa = haima = haema. Haemophilus is correctly spelled ; Hemophilus is not a 
"simplified spelling" but an incorrectly spelled modern Latin word. 

One finds many errors of transliteration in bacteriological nomenclature. If 
corrected, the words should be regarded as alternative spellings (variants) of 
the same word and not as two different words. 

Sometimes there are incongruities in transliteration of Greek into Latin form 
in a single word. For example, the specific epithet of the species Micrococcus lyso- 
deikticus is an interesting mixture. The second component of the word is the Greek 
8hktlk6(7. The first letter, delta (5), is d; the second, epsilon (e), is short e; the third 
(and sixth), iota (t), is short i; the fourth (and seventh) is kappa (k), the Latin c; 
the eighth, omicron (o), is short o; and the final, sigma (a-), is s. The Latins used 
i for the diphthong et. There is no k in the Latin alphabet. The masculine ending 
OS in Greek becomes us in Latin. Hence, beiKTiKocr = deicticos = dicticus. Correct 
transliteration would have given lysodicticus instead of the current lysodeikticus. 

However, in general, it is well to observe the rule that the original spelling of 
the word be conserved, unless it can be regarded definitely as a slip of the pen. 

A few generic names have been so commonly incorrectly accented as to consti- 
tute accepted exceptions. Several examples may be cited. 

Many generic names in bacteriology and protozoology have as the final com- 
ponent -monas, as Pseudomonas and Xanthomonas. The Greek word is nopas. 
The first vowel is short. Correct accentuation would give Pseu.do'mo.nas, Xan.- 
tho'mo.nas, etc. with the accent on the antepenult. There is a tendency to regard 
the as long and to place the accent on the penult, giving Pseu.do.mo'nas, the 
pronunciation accepted by such dictionaries as Century and Borland. 



28 HOW BACTERIA ARE NAMED AND IDENTIFIED 

Again, many Modern Latin names of taxa have -myces as the last component. 
The Greek is ixvK-q'i = myces in which the first vowel is definitely short. In these 
generic names the accent would seem properly to be on the antepenult, as Ac- 
ti.no'my.ces and Strep.to'my.ces. The commonly accepted accentuation is 
Ac.ti.no. my' ces and Strep . to . my'ces. 

There is also some confusion relative to syllabication and accentuation in 
Modern Latin names of taxa ending in -oides. The derivation of the ending makes 
it evident that the oi is not a diphthong, and the o and i should be differentiated 
and separately pronounced. For example, the generic name Bacteroides should 
be syllabicated and accented Bac.te.ro.i'des. There has been confusion with the 
English diphthong oi, and pronunciation with one less syllable, Bac.te.roi'des, has 
been recognized. 

Abbreviations . The following areviations are used in the Manual in giving 
derivations. 

Gr. = Greek. The original Greek spelling is not given in the Manual. As noted 
above, the word is transliterated into the Latin alphabet; the gender endings of 
the Greek are changed usually to the Latin gender endings of the corresponding 
Latin declension. This makes evident the stems* that may be used in construction 
of the Modern Latin names. Gr. means latinized Greek. 

L. = Latin. Usually this indicates that the word is one used in classic Latin 
(or in some cases post-classic Latin) and found in an unabridged Latin dictionary. 

M.L. = Modern Latin. A word used as the name of a taxon or as a specific 
epithet, to be treated and used as a Latin word, of various derivations but not 
classic Latin. 

Med. L. = Medieval (sometimes pharmaceutical) Latin. Many words derived 
from languages other than Latin were Latinized during the middle ages and uti- 
lized in fields such as pharmacy, alchemy and biology. Some Modern Latin names 
are derived from these. 



fem. 


= feminine gender. 


n. = 


noun. 


mas. 


= masculine gender. 


part. 


adj. = particip 


neut. 


= neuter gender. 


V. = 


verb. 


part. 


= participle. 


nom. 


= nominative. 


adj. ■■ 


= adjective. 


gen. 


= genitive. 



pi. = plural. Note that the names of all taxa higher than the genus are plural 
and have plural endings, as Bacillaceae, Actinomycetales. 

* The stem to be used in making compounds is not always complete in the nominative. 
It is found by dropping the genitive ending. For example, the generic name Actinomyces 
has as the genitive, Actinomycetis ; the stem used in compounds is Actinomycet-, hence the 
famil}^ name eerived from Actinomyces is Actinomycetaceae, not Actinomycaceae. Note 
should be taken of the fact that all Greek words that end in -ma are neuter and have as 
genitive -malis. The stem combining form) always ends in mat. For example Treponema, 
gen. Treponematis, has as its stem Treponemal- from which one may derive a family name 
Treponemataceae (not Treponemaceae) . 



DIVISION I. PROTOPHYTA* SACHS, 1874, EMEND. 
KRASSILNIKOV, 1949. 

(Sachs, Lehrbuch der Botanik, 4 Aufl., 1874, 249; Schizophyta Cohn, Beitr. z. Biol. d. 
Pflanzen, /, Heft 3, 1875, 202; Krassilnikov, Guide to the Bacteria and Actinomycetes, Izd. 
Akad. Nauk, U.S.S.R., Moskau, 1949, 41.) 

Pro.to.phy'ta. Gr. combining form protos first (in time), primordial; Gr. noun phylum 
plant; M.L. pi. noun Protophyta primordial plants. 

Unicellular organisms and organisms which occur in trichomes. Generally these forms 
are too small to be distinguishable to the naked eye. Ordinarily no differentiation of cells 
is evident, although those forms that occur in trichomes may show some differentiation 
into vegetative and specialized cells of various types (heterocysts, holdfast cells and re- 
productive cells). Increase in number of individual cells is normally effected by simple cell 
division (fission), rarely by budding; however among the most highly advanced forms, 
spores of various types may be developed (endospores, conidia or gonidia). In the highly 
specialized parasites such as the viruses, the processes of reproduction have become so 
intimately associated with the living protoplasm of the host cells, and the virus particles 
are so minute (less than 200 millimicrons in diameter) that the e.xact method of reproduction 
has not yet been determined with certainty. For many years it was believed that these 
organisms do not possess nuclei; however, in recent years simple types of nuclear bodies 
have been demonstrated in many of these organisms, and a nucleus, or at least definite 
nuclear material (chromatin), has been found to be present in all cases. Do not contain 
chloroplastids, which are found in the cells of the green portions of higher plants. Ubiqui- 
tous, occurring in the air, everywhere on the surface of the earth, in and on plants and ani- 
mals and even far below the surface of the earth in mine waters. 

Key to the classes of division Protophyta. 

I. Organisms which possess the photosynthetic pigment phycocyanin in addition to 
chlorophyll. 

Class I. Schizophyceae, p. 30. 
II. Organisms which usually do not contain photosynthetic pigments. None contain phyco- 
c\'anin. 

A. Reproduction by fission. Cells not normally filterable, though filterable stages are 
known in some species. 

Class II. Schizomycetes, p. 33. 

B. Cells so minute that the exact form of reproduction is not clearly understood as yet. 
All possess filterable stages. 

Class III. Microtatobiotes, p. 931. 

* The sections which characterize the Division Protophyta, the classes, the orders and in 
some cases the families have been prepared by Prof. Robert S. Breed, Cornell University, 
Geneva, New York. 



29 



CLASS I. SCHIZOPHYCEAE COHN, 1879. 

(Myxophyceae Stizenberger, 1860; Phycochromophyceae Hahenhorst, 18G3 -jCyanophyceen 
Sachs, Lehrbuch der Botanik, 4 Aufl., 1874, 249; Cohn, Jahresber. Schles. Ges. f. vaterl. 
Cultur, f. 1879, 279-289.) 

Schi.zo.phy'ce.ae. Gr. noun schizo cleft, fission; Gr. noun phycus seaweed, alga; M.L. 
pi. noun Schizophyceae fission algae. 

The organisms in this class are usualh' designated as the blue-green algae and are studied 
in connection with other types of algae (green, brown and red) and the higher fungi in 
courses in Cryptogamic Botany. However, the blue-green algae differ structurally from all 
other types of Thallophyta. On the other hand they resemble the bacteria so that the blue- 
green algae and the bacteria are commonly classed in the same Division of the Plant King- 
dom. 

In order to identify the species of blue-green algae, consult any of the following books: 

O. Kirchner, Schizophyceae, in Engler and Prantl, Die Natiirlichen Pflanzenfamilien, I 
Teil, Abt. la, 1900, 45-92; Gilbert H. Smith, Cryptogamic Botany, 2nd ed.. Vol. 1, Algae 
and Fungi, New York, 1955, 526 pp.; Gilbert H. Smith, Freshwater Algae of the United 
States, New York, 1950, 719 pp. 

The Schizophyceae are not described further in the present Manual. 




CLASS II. 
SCHIZOMYCETES VON NAEGELI 



By 
ROBERT S. BREED 

Late Professor Emeritus, Cornell University, Geneva, New York 

E. G. D. MURRAY 

Research Professor, University of Western Ontario, 
London, Ontario, Canada 

NATHAN R. SMITH 

Senior Bacteriologist, Retired, Plant Industry Station, U. S. Department 
of Agrictdture, Beltsville, Maryland 

and 

Specialists whose names appear on the following pages 
in connection with the sections prepared by them 



CLASS II. SCHIZOMYCETES VON NAEGELI, 1857. 

(Von Naegeli, Bericht Verhandl. d. bot. Section d. 33 Versammling deutsch. Naturfonsch. 
u. Arzt. Bot. Ztg., 1857, 760; Bacterien, Cohn, Beitr. z. Biol. d. Pflanzen, /, Heft 2, 1872, 
127; Bacteriaceae Cohn, Arch. f. path. Anat., 55, 1872, 237; Schizomijcetaceae DeToni and 
Trevisan, in Saccardo, Sylloge Fungorum, 8, 1889, 923; Bacteriales Clements (as an ordinal 
name), The Genera of Fungi, Minneapolis, 1909, 8; Schizomycetacea Castellani and Chal- 
mers, Manual of Tropical Medicine, 3rd ed., 1919, 924; Mychota Enderlein, Bakterien- 
Cyclogenie, 1924, 236; Schizotnyceiae Stanier and van Niel, Jour. Bact., 4^, 1941, 458). 

Schi.zo.m\-.ce'tes. Or. noun schiza cleft, fission; Gr. noun myces, mycetis fungus; 
M.L. mas. pi. n. Schizomycetes the class of fission fungi. 

Tj'pically unicellular plants. Cells usually small, sometimes ultramicroscopic. Fre- 
quently motile. For many years it was thought that the cells of Schizomycetes and of the re- 
lated Schizophyceae did not possess the nucleus invariably found in the cells of other plants. 
However, using modern cytological techniques, investigators have now demonstrated a 
true nucleus in bacterial cells. Individual cells maj- be spherical or straight, curved or spiral 
rods. These cells may occur in regular or irregular masses, or even in cysts. Where they re- 
main attached to each other after cell division, they may form chains or even definite 
trichomes. The latter may show some differentiation into holdfast cells and into motile 
or non-motile reproductive cells. Some grow as branching mycelial threads whose diameter 
is not greater than that of ordinary bacterial cells, i.e., about one micron. Some species 
produce pigments. The true purple and green bacteria possess pigments much like or related 
to the true chlorophylls of higher plants. These pigments have photosynt^etic properties. 
The phycocyanin found in the blue-green algae does not occur in the Schizomycetes . Multi- 
plication is typically by cell division. Endospores are formed by some species included in 
Eubacteriales. Sporocj'sts are found in Myxobacterales. Ultramicroscopic reproductive 
bodies are found in Myco-plasmaiales . The bacteria are free-living, saprophytic, parasitic or 
even pathogenic. The latter t3-pes cause diseases of either plants or animals. Ten orders 
are recognized. 

Key to the orders of class Schizomycetes. 

I. Cells rigid. Spherical, rod-shaped (straight or curved) or spiral in form. Sometimes in 
trichomes. Motile by means of polar flagella or non-motile. 

A. Cells coccoid, straight or curved rods, or spiral in foi-m. Sometimes occur as chains 
of cells. Cells may contain photosynthetic purple or green pigments. Not in tri- 
chromes. Usually motile by means of polar fiagella. Occasionally non-motile. 

Order I. Pseudomonadales, p. 35. 

B. Not as above. 

1. Cells in trichomes that are frequentl}' in a sheath. Occasionally motile (swarm 
spores) or non-motile conidia are developed. The sheaths may contain a deposit 
of ferric hydroxide, and the trichomes may be attached to a substrate. 

Order II. Chlamydohacteriales , p. 262. 

2. Cells reproduce by a process of budding rather than by ordinary cell division (fis- 
sion). May be attached to a substrate by a stalk. One genus contains species with 
photosynthetic pigments {Rhodomicrobium) . 

Order III. Hyphomicrobiales , p. 276. 
II. Not as above. 

A. Cells rigid. Spherical or straight rod-shaped cells. Occur singly, in chains or in tri- 
chomes. Motile by means of peritrichous flagella or non-motile. Not acid-fast. 
1. Cells spherical or rod-shaped; no trichomes though chains of cells may occur. 

Order IV. Eubacteriales, p. 281. 

33 



34 ORDER I. PSEUDOMONADALES 

2. Cells in trichomes. 

Order VI. Caryophanales, p. 830. 
B. Not as above. 

1. Cells rigid and maj- grow out into a branching mycelium-like .structure which 
may even develop chains of aerial conidia giving colonies a superficial resem- 
blance to mold colonies. In two genera spores develop within sporangia (sporan- 
giospores), and in one of these genera the spores are motile. Where cells occur 
singly or in simple branched forms, they are frequently acid-fast. 

Order V. Actinomycetales, p. 694. 

2. Not as above. 

a. Cells rigid, usually large and may occur as coccoid cells or trichomes. Sulfur 
granules may occur on the surface or within the cells. Move by a gliding, oscil- 
lating or rolling, jerky motion like that of some blue-green algae. No flagella 
present. 

Order VII. Bcggiatoales, p. 837. 
aa. Not as above. 

b. Longer or shorter flexuous cells. 

c. Cells flexuous, creeping on a substrate. Frequentlj^ pointed at both 
ends. Fruiting bodies are usually developed from a thin spreading 
colony (pseudoplasmodium). Slime bacteria. 

Order VIII. Myxobacterales, p. 854. 
cc. Cells in the form of longer or shorter spirals. Swim freely by flexion of 
cells. 

Order IX. Spirochaetales, p. 892. 
bb. Non-motile, highly pleomorphic organisms of a very delicate character. 
Possess filterable stages. 

Order X. Mycoplasmatales, p. 914. 



ORDER I. PSEUDOMONADALES ORLA -JENSEN, 1921. 



(Jour. Bact., 6, 1921, 270.) 

Pseu.do.mo.na.da'les. M.L. fern. pi. n. Pseudomonadaceae type family of the order; -ales 
ending to denote an order; M.L. fem.pl.n. Pseudomonadales the Pseudomonadaceae order. 

Straight, curved or spiral, rigid, rod -shaped bacteria. Rarely occur in pairs or chains. 
The cells in a few species are ellipsoidal and are frequently spoken of as being coccoid or 
even spherical in form. They are usually about 1.0 micron in diameter, but in a few species 
the individual cell is larger than is normal for bacterial cells, reaching a size of 3.0 to 14.0 
microns in diameter and as much as 100 microns in length. The cells are usually polar flagel- 
late. When motile they sometimes bear a single flagellum, in other cases a tuft of flagella. 
The flagella are normally found at one or both ends of the cell, but in one genus the curved 
cells bear a tuft of flagella that is attached in the middle of the concave side (Selenomonas) . 
Non-motile species whose characteristics indicate that thej' belong in this order with closely 
related, motile species occasionally occur. Cells are Gram-negative so far as known. The 
cells in one sub-order contain pigments that have the power of photosynthesis. The cells 
in the second sub-order lack such pigments, as do all other groups of bacteria. The cells 
in the first sub-order are photo-autotrophic, while chemo-autotrophic species occur in the 
second sub-order. Energy is frequently secured by oxidative processes though there are also 
many species that show a fermentative physiology. Cells quite frequently occur in zoogloeal 
masses. No endospores are found, and reproduction is by means of fission. Many species 
occur in coastal, swamp and pond waters and in soil. Some are parasitic and some are even 
pathogenic, causing diseases of fishes and other cold-blooded vertebrates. There are a few 
species (cholera, blue pus, etc.) that cause diseases of warm-blooded mammals, including 
man. 

Kerj to the sub -orders of order Pseudomonadales. 

I. Cells contain red, purple, brown or green photosynthetic pigments. Sometimes also 
enclose granules of free sulfur. 

Sub-order I. Rhodobacteriineae , p. 35. 
II. Cells do not contain photosynthetic pigments, although they may produce greenish, 
brownish, rose or yellow, diffusible, water-soluble pigments or yellow or red non-water- 
soluble pigments. Free sulfur granules may occur within or without the cells (Thio- 
bacteriaceae). Ferric hydroxide may be deposited (Caulobacteriaceae) . 

Sub -order II. Pseudomonadineae, p. 67. 



Suborder I. Rhodobacteriineae Breed, Murray and Kitchens, 1944.* 

(Family Rhodobacteriaceae Migula, Syst. d. Bakt., 2, 1900, 1042; Breed, Murray and 
Hitchens, Bact. Rev., 8, 1944, 257.) 

Rho.do.bac.te.ri.i'ne.ae. M.L. neut.n. Rhodobacteriuin a genus of bacteria; -ineue end- 
ing to denote a suborder; M.L. fem.pl.n. Rhodobacteriineae the Rhodobacterium suborder. 

* Rearranged and revised by Prof. C. B. van Niel, Hopkins Marine Station, Pacific 
Grove, California, July, 1953. 

35 



V 



36 ORDER I. PSEUDOMONADALES 

Cells spherical, rod-, vibrio- or spiral-shaped. Diameter of individual cells from less than 
1.0 to over 10 microns. Red, purple, brown or green bacteria which contain bacteriochloro- 
phj-ll or other chloroph3dl-like green pigments, and which usually also possess one or more 
carotenoid pigments. Capable of carrying out a photosynthetic metabolism which differs 
from that of green plants in that it does not proceed with the evolution of oxygen, and de- 
pends upon the presence of extraneous oxidizable compounds which are dehydrogenated 
with the simultaneous reduction of carbon dioxide. As oxidizable substrates, a varietj' of 
simple substances can be used, such as sulfide, or other reduced sulfur compounds, molecu- 
lar hydrogen, alcohols, fatty acids, hydroxy- and keto-acids, etc. All can be grown in 
strictly anaerobic cultures when illuminated. Those members which can grow in the pres- 
ence of air can also be cultured in the dark under aerobic conditions. Color depends mark- 
edly on environmental conditions; small individuals appear colorless unless observed in 
masses. May contain sulfur globules. Described species have largely been found in fresh- 
water habitats. Some species occur in marine habitats. 

Key to the families of suborder Rhodobacteriineae. 

I. Purple bacteria whose pigment system consists of bacteriochlorophyll and various 
carotenoids capable of carrying out a photosynthetic metabolism. 

A. Contain sulfur globules in the presence of hj'drogen sulfide. The sulfur purple bac- 
teria. 

Family I. TJiiorlwdaceae, p. 38. 

B. Do not contain sulfur globules even in the presence of hydrogen sulfide. All require 
organic growth factors. The non-sulfur purple and brown bacteria. 

Family II. Athiorhodaceae, p. 53. 
II. Green sulfur bacteria containing a pigment system which has the characteristics of a 
chlorophyllous compound although it differs from the chlorophyll of green plants and 
from the bacteriochlorophyll of the purple bacteria. 

Family III. Chlorobacteriaceae , p. 61. 

The organisms previously included in the order Thiohacteriales Buchanan do not consti- 
tute a taxonomic entity; they represent rather a physiological-ecological community. In 
this sense, however, a special treatment of this group as a unit has decided advantages from 
a determinative point of view. 

When first proposed as a systematic assemblage, the order Thiobacferia Migula (Sj'st. d. 
Bakt., 3, 1900, 1039) was intended to include the morphologically conspicuous organisms 
which, in their natural habitat, contain globules of sulfur as cell inclusions. Since Wino- 
gradsky (Beitr. z. Morph. u. Physiol, d. Bact., I, Schwefelbacterien, 1888) had elucidated 
the function of hydrogen sulfide and of sulfur in their metabolism, the characteristic inclu- 
sions appeared linked with a hitherto unrecognized type of physiology, viz. the oxidation 
of an inorganic substance instead of the decomposition of organic materials. From this 
oxidation the sulfur bacteria derive their energy for maintenance and growth. 

Two groups of sulfur bacteria could be distinguished, one consisting of colorless, the 
other of red or purple organisms. The members of both groups presented an unusual mor- 
phology apart from the sulfur droplets : in all cases the individual cells were considerably 
larger than those of the common bacteria, while many species grew as distinctive colonial 
aggregates. Migula separated these sulfur bacteria into two families, Beggiatoaceae and 
Rhodobucteriaceae. Even at that time, however, some difficulties e.xisted as to just what 
organisms should properly be considered as sulfur bacteria. Miyoshi (Jour. Coll. Sci., Imp. 
Univ., Tokyo, 10, 1897, 143) had discovered a bacterium which forms strands, incrusted with 
sulfur, in sulfur springs but which does not store sulfur globules in its cells. Although 
physiologically this organism appeared to comply with Winogradsky's concept of a sulfur 
bacterium, the absence of the typical cell inclusions made Miyoshi decide it could not be 



ORDER I. PSEUDOMONADALES 37 

considered as such. The problem was aggravated when Nathansohn, Beijerinck and Jacob- 
sen published their studies on small, colorless, Psendomonas-like bacteria capable of oxidiz- 
ing hydrogen sulfide, sulfur and thiosulfate, and evidently dependent upon this oxidation 
process for their development. Morphologically these organisms have little in common with 
the Beggiatoaceae; they were designated by Beijerinck as species of Thiobacillus and have 
since been rightly considered as members of the order Psendomonndales (see p. 35). Never- 
theless, these organisms are physiologically in no way different from the Beggiatoaceae, so 
that if phj'siology only is considered, a good case could be made out for their incorporation 
in the Thiohacterinles. 

Furthermore, Molisch (Die Purpurbakterien, Jena, 1907, 95 pp.) described in some de- 
tail a number of bacterial species which, in view of their characteristic pigment system, 
appeared closely related to the Rhodobacieriaceae , but which develop only in organic media 
and are, therefore, not sulfur bacteria in the sense of Winogradsk\' or Migula. In stressing 
the importance of pigmentation, Molisch combined the red sulfur bacteria and the newly- 
discovered purple bacteria into an order Rhodobacteria with the two families Thiorhodaceae 
and Athiorhodaceae . It is this grouping that has been followed in the present edition of the 
Manual. 

Among the non-sulfur purple bacteria, or Athioihodaceae, is included an organism which, 
on the basis of its morphology and manner of growth, does not conform to the criteria of 
the order Pseudornonadalcs . This is Rhodomicrobium vannielii Duchow and Douglas (Jour. 
Bact., 58, 1949, 409). Physiologically it is a typical non-sulfur purple bacterium in that it is 
capable of development in strictly anaerobic media supplied with an appropriate oxidizable 
substrate only when the cultures are illuminated and carries out a photosynthetic metabo- 
lisii without oxygen evolution. Multiplication is not, however, by transverse fission but by 
bud formation at the end of a thin filament growing out of a pole of the mother cell followed 
by the formation of a cross wall in the connecting filament. This mode of development is 
similar to that encountered in the non-photosynthetic bacterium Htjphomicrobium vulgare. 

It should also be emphasized here that some of the sulfur purple bacteria (Thiopedia, for 
example) and all of the green sulfur bacteria appear at present to be pernianentlj- immotile. 

Only a very small number of t^'pical sulfur bacteria have been studied in pure cultures. As 
a result the descriptions of genera and species rest mainly on observations made with 
collections from natural sources or crude cultures. Most investigators have implicitly ac- 
cepted differences in cell size or in colonial appearance as a sufficient justification for es- 
tablishing independent species. Evidently this procedure presupposes a considerable degree 
of constancy of such characteristics in the organisms in question. It is true that Wino- 
gradskj^'s investigations have provided a reasonable basis for this belief, but later studies 
with pure cultures of certain purple bacteria have established beyond a doubt that environ- 
mental conditions, such as composition of the medium and temperature, may exert a pro- 
found influence on the general morphology of these organisms. By this it is not intended to 
infer that the previously proposed genera and species of sulfur bacteria should be aban- 
doned, but it does follow that a cautious evaluation of the distinguishing features is neces- 
sary. In the absence of carefully conducted investigations on morphological constancy and 
variability of most of the previously recognized species of sulfur bacteria with pure cultures 
grown under a variety of external conditions, the best approach appears to be a tentative 
arrangement of these organisms based upon those characteristics which are readily ascer- 
tainable. Experience with this group over the past twenty-five years has shown that, while 
Winogradskj^'s fundamental work must remain the foundation of present taxonomic ef- 
forts, it is advisable to simplifj' the much more elaborate classification developed by Bu- 
chanan which was followed in previous editions of this Manual. 

Certain genera of sulfur purple bacteria, created by Winogradsky, will very probably be 
consolidated when detailed information concerning the morphology of the organisms is 
available. Until such time it seems, however, best toj-etain most of them, even though the 



38 ORDER I. PSEUDOMONADALES 

distinguishing characteristics are not always very clear. For the benefit of those who are 
familiar with previous methods of classification, it will be indicated where deviations have 
been adopted. 

The non-sulfur purple bacteria {Athiorhodacene Molisch; Rhodobacterioideae Buchanan) 
have been subjected to a comparative morphological and physiological study comprising 
more than 150 strains, among which all previously proposed genera and species are repre- 
sented (van Niel, Bact. Rev., 8, 1944, 1-118). It has been found that the characteristics 
upon which Molisch based the seven genera of this group are inadequate, and a new classi- 
fication with only two distinguishable genera has been proposed. This system will be fol- 
lowed here. 

Nadson (Bull. Jard. Imper. Bot., St. Petersburg, 13, 1912, 64) described a new type of 
small, green bacteria not containing sulfur globules in the presence of hydrogen sulfide but 
excreting elemental sulfur. They arephotosynthetic and are capable of growing in anaerobic 
culture when illuminated. The green pigment differs from the green plant chlorophylls and 
from the bacteriochlorophyll of the purple bacteria but has the characteristics of a chloro- 
phyllous compound. These are grouped in the family Chlorobacteriaceae. 



FAMILY I. THIORHODACEAE MOLISCH, 1907. 
(Die Purpurbakterien, Jena, 1907, 27.) 

Thi.o.rho.da'ce.ae. Gr. noun thium sulfur; Gr. noun rhodum the rose; -aceae ending to 
denote a family; M.L. fem.pl.n. Thiorhodaceae (probably intended to mean) the family of 
sulfur red bacteria. 

Unicellular organisms, often developing as cell aggregates or families of variable size 
and shape. Single cells have the form of spheres, ovoids, short rods, vibrios, spirals, long 
rods or, occasionally, chains. Thej^ occur in nature in environments containing sulfides and 
require light for their development; infra-red irradiation of a wave-length extending to 
about 900 millimicrons is effective. They produce a pigment system composed of green bac- 
teriochlorophyll and yellow and red carotenoids. As a result they appear as bluish violet, 
pale purple, brownish to deep red cell masses. Single cells, unless they are of considerable 
size, usually appear to be unpigmented. These are anaerobic or microaerophilic organisms 
with a photosynthetic metabolism in which carbon dioxide is reduced with the aid of spe- 
cial hydrogen donors without the liberation of molecular oxygen. Where these organisms 
are found in nature, hydrogen sulfide acts as a hydrogen donor, and sulfur, the first inter- 
mediate oxidation product, accumulates as sulfur droplets in the cells. Probably all mem- 
bers of the group can utilize a number of organic substances in place of hydrogen sulfide as 
hydrogen donors for photosynthesis. Thus they are potentially mixotrophic. 

Characterization of the genera in this group has, since Winogradsky's studies (Beitrage 
zur Morphologie und Physiologie der Schwefelbacterien, Leipzig, 1888), been based upon 
the mode of development of the cell aggregates. Pure-culture studies (Bavendamm, Die 
farblosen und roten Bakterien, I. Schwefelbakterien, Pflanzenforschung, Heft 2, 1924, 74 
pp.; van Niel, Arch. f. MikrobioL, 3, 1931, 1-112; Manten, Antonie van Leeuwenhoek, 8, 
1942, 164 pp.) have shown, however, that not only the sequence of events in the formation 
of the aggregates but also the appearance and form of the latter, even including the size 
and shape of the component cells, are influenced to a considerable extent by environmental 
conditions. This obviously casts doubt upon the usefulness of the previously used diag- 
nostic criteria for genera and species. On the other hand, the scope of pure-culture studies 
has not yet attained sufficient breadth to warrant the use of a different approach. As a 
provisional measure, Winogradsky's genera are therefore maintained. Even the larger 
taxonomic units must be regarded as being of tentative value only. 



FAMILY I. THIOEHODACEAE 6\) 

Key to the genera of family Thiorhodaceae. 

I. Cells usually combined into aggregates. 

A. Cells grouped as regular sarcina packets. 

Genus I. TMosarcina, p. 39. 

B. Cells not in sarcina packets. 

1. Aggregates in the form of a flat sheet. 

a. Cells in regular arrangement, with tetrads as the common structural unit. 
Genus II. Thiopedia, p. 40. 
aa. Cells in irregular aggregates. 

Genus III. Thiocapsa, p. 41. 

2. Aggregates in the form of three-dimensional masses. 

a. Cells distinctly rod-shaped and arranged in a net-like structure. 
Genus IV. Thiodictyon, p. 41. 
aa. Cells not so arranged. 

b. Cells in a common capsule, individuals rather scattered and loosely 
grouped. 

Genus V. Thiothece, p. 42. 
bb. Cells in rather dense clumps. 

c. Aggregates embedded in conspicuous common slime capsule. 

d. Aggregates small, compact, often several of them enclosed to- 
gether in a common capsule. 

Genus VI. Thiocystis, p. 42. 
dd. Aggregates large and solid, later break up into small clusters. 
Genus VII. Lamprocystis , p. 43. 
cc. Common capsule lacking or verj^ transient. 

d. Aggregates as a whole exhibit amoeboid movements. 
Genus VIII. Amoebobacter, p. 44. 
dd. Aggregates devoid of amoeboid movements. 

Genus IX. Thiopoly coccus, p. 45. 
II. Cells usually occurring singly. 

A. Cells clearly spiral-shaped. 

Genus X. Thiospirillum, p. 46. 

B. Cells not spiral-shaped. 

1. Cells irregular, often swollen, distorted, or composed of long, crooked and bent 
rods to filaments. 

Genus XI. Rhabdomonas , p. 48. 

2. Cells regular, spherical to short rods or bean-shaped. 

a. Cells spherical, as a rule non-motile, and each one surrounded by a rather 
wide capsule. 

Genus XII. Rhodothece, p. 50. 
aa. Cells ellipsoidal, ovoid, short rods or vibrios, actively motile. 
Genus XIII. Chromatium, p. 50. 

Genus I. Thiosarcina Winogradsky, 1888. 

(Zur Morphologie und Phj'siologie der Bacterien, I. Schwefelbacterien, Leipzig, 1888, 
104.) 

Thi.o.sar.ci'na. Gr. noun thium sulfur; M.L. fem.n. Sarcina a genus of bacteria; M.L. 
fem.n. Thiosarcina sulfur Sarcina. 

Individual cells spherical, forming regular cubical packets of sarcina-shape, resulting 
from consecutive division in three perpendicular planes. Packets commonly containing 
8 to 64 cells. Infrequently motile. Non-spore-forming. Contain bacteriochlorophyll and 



40 



ORDER I. PSEUDOMONADALES 



earotenoid pigments, hence, pigmented purplish to red. Capable of carrying out a photo- 
sj'nthetic metabolism in the presence of hydrogen sulfide, cells then storing sulfur globules. 
Anaerobic. 

The type species is Thiosarcina rosea (Schroeter) Winogradsky. 



1. Thiosarcina rosea (Schroeter, 1886) 
Winogradsky, 1888. (Sarcina rosea Schroeter , 
Kryptog. -Flora von Schlesien, 3, 1, 1886, 154; 
Winogradsky, Zur Morphologie und Physio- 
logic der Schwefelbacterien, Leipzig, 1888, 
104.) 

ro'se.a. L. adj. roseus rosy, rose-colored. 

Cells spherical, 2 to 3 microns in diameter, 
occurring in packets containing 8 to 64 cells. 
Infrequently motile. Color ranging from 
purplish rose to nearly black. 



Anaerobic. 

Habitat : Occur less frequently than other 
sulfur purple bacteria; probably widely dis- 
tributed in mud and stagnant bodies of 
water containing hydrogen sulfide and ex- 
posed to light; sulfur springs. 

Illustration: Issatchenko, Recherches sur 
les microbes de I'ocean glacial arctique, 
Petrograd, 1914, Plate II, fig. 5. 



Genus II. Thiopedia Winogradsky , 1888. 

(Zur Morphologie und Physiologie der Bacterien, I. Schwefelbacterien, Leipzig, 18S8, 85.) 

Thi.o.pe'di.a. Gr.n. thium sulfur; Gr.n. pedium a plain, a flat area; M.L. fem.n. Thio- 
pedia a sulfur plain. 

Individual cells spherical to short rod-shaped, the latter shortly before cell division. 
Arranged in flat sheets with typical tetrads as the structural units. These arise from divi- 
sions of the cells in two perpendicular directions. Cell aggregates of various sizes, ranging 
from single tetrads to large sheets composed of thousands of cells. Non-motile. Non-spore- 
forming. Contain bacteriochlorophyll and earotenoid pigments. Capable of photosynthesis 
in the presence of hydrogen sulfide, then storing sulfur globules. Anaerobic. 

The type species is Thiopedia rosea Winogradsky. 



1. Thiopedia rosea Winogradsky, 1888. 
(Erythroconis littoralis Oersted, Naturhist. 
Tidsskrift, 3, 1840-1841, 555; Winogradsky, 
Zur Morphologie und Physiologie der 
Schwefelbacterien, Leipzig, 1888, 85.) 

ro'se.a. L. adj. roseus rosy, rose-colored. 

Cells 1 to 2 microns, often appearing as 
slightly elongated cocci regularly arranged 
in platelets. 

Color, pale red to nearly black, depending 
upon the amount of sulfur stored. Red color 
visible only with large cell masses, not in 
individuals. 

According to Winogradsky, the cells are 
often embedded in a common slime capsule; 
the e.xtensive studies of Utermohl (Archiv f . 
Hydrobiol., Suppl. Vol. 5, 1925, 251-276) 
make the regular occurrence of such cap- 
sules extremely doubtful. On the other 
hand, Utermohl emphasizes as quite charac- 



teristic the common presence of a relatively 
large pseudovacuole, or aerosome, in the 
cells of this species encountered in plankton 
samples. Winogradskj^ does not mention 
this; nevei-theless, it appears to be a regular 
and valuable distinguishing feature. 

Anaerobic. 

Habitat: Widely distributed in mud and 
stagnant bodies of fresh, brackish and salt 
water containing hydrogen sulfide and ex- 
posed to light; sulfur springs. Common, 
frequently giving rise to very extensive 
mass developments. 

Illustrations: Warming, Videnskab. 
Meddel. naturhist. Forening, Kjobenhavn, 
1876, Plate VIII, fig. 2; Winogradsky, op. 
cit., 1888, 85, Plate III, fig. 18; Pringsheim, 
Naturwissensch., £0, 1932, 481, the last one 
a truly excellent photomicrograph. 



FAMILY I. THIORHODACEAE 41 

Genus III. Thiocapsa Winogradsky, 1888. 

(Schwefelbacterien, Leipzig, 1888, 84.) 

Thi.o.ca'psa. Gr.n. ihiiun sulfur; L.n. capsa a box; M.L. fem.n. Thiocapsa sulfur box. 

Cells spherical, occurring in families of irregularly arranged individuals held together 
in a common slime capsule. The aggregates are spread out flat on the substrate. Motility 
not observed. As the colony grows, the capsule bursts, and the cells are spread apart. Gen- 
eral morphology and development thus appear similar to that in the genus Aphanocapsa 
among the blue-green algae. Contain bacteriochlorophyll and carotenoid pigments; capable 
of photosynthesis in the presence of hydrogen sulfide. Under such conditions sulfur is stored 
in the form of globules in the cells. This genus is so much like TMothece that it is doubtful 
whether a distinction can be maintained. 

The type species is Thiocapsa roseopersicina Winogradskj'. 

Key to the species of genus Thiocapsa. 

I. Individual cells about 3 microns in diameter. 

1. Thiocapsa roseopersicina. 
II. Individual cells about 1.5 microns in diameter. 

2. Thiocapsa floridana. 

1. Thiocapsa roseopersicina Winograd- Illustration: Winogradsky, loc. cit., Plate 

sky, 1888. (Schwefelbacterien, Leipzig, 1888, IV, fig. 15. 

• •/ T J- 2. Thiocapsa floridana Uphof, 1927. 

ro.se.o.per.si.ci na. L. adj. roseus rosy; tt i u- i ^ 



Gr. noun persicus the peach, Persian apple, 
Persian; M.L. adj. roseopersicinus rosy- 



(Arch. f. Hydrobiol., 18, 1927, 84.) 

flo.ri.da'na. M.L. adj . floridanus pertain- 
ng to Florida. 



^^^.. , ■ 1 r. r o • • 1- Cells spherical, about 1.5 microns in di- 



Cells spherical, 2.5 to 3 microns in diam- 



ameter. In groups of irregular colonies, each 



eter, occurring in families of irregularly ,,,j.rounded by a common capsule, several 

arranged individuals held together in a colonies being stuck together. Motility not 

common slime capsule. Motility not ob- observed 

served. Usually a distinct rose-red. Stored Source: Palm Springs, Florida and Lake 
sulfur droplets may attain a considerable Sakskoje, near Eupatoria, Crimea, 
size. Habitat: Mud and stagnant water con- 
Habitat: Mud and stagnant bodies of taining hydrogen sulfide and exposed to 
water containing hydrogen sulfide and ex- light; sulfur springs. Probably ubiquitous, 
posed to light; sulfur springs. Illustration: Uphof, ibid., 83, fig. VI. 

Genus IV. Thiodictyon Winogradsky, 1888. 

(Winogradsky, Schwefelbacterien, Leipzig, 1888, 80; Rhododictyon Orla-Jensen, Cent. f. 
Bakt., II Abt., 22, 1909, 334.) 

Thi.o.dic'ty.on. Gr. noun thium sulfur; Gr. noun dictyum or dictyoii net; M.L. neut.n. 
Thiodictyon sulfur net. 

Cells rod-shaped, frequently with pointed ends, somewhat resembling spindles. Form 
aggregates in which the cells become arranged end to end in a net-like structure, somewhat 
reminiscent of the shape of the green alga Hydrodictyon. The shape is not constant; cells 
may also form more compact masses. Sometimes groups of cells separate from the main 
aggregate by active movements. Common gelatinous capsule not observed. Contain bac- 
teriochlorophyll and carotenoid pigments; cells usually very faintly colored. Capable of 
photosynthesis in the presence of hydrogen sulfide, the cells then storing sulfur as small 
globules. 



42 ORDER I. PSEUDOMONADALES 

The type species is Thiodictyon elegans Winogradsky. 

1. Thiodictyon elegans Winogradsky, Issatchenko (Etudes niicrobiologiques des 

1888. (Schwefelbacterien, Leipzig, 1888, 80.) Lacs de Boue, Leningrad, 1927, 113-114) 

e'le.gans. L. adj. elegans choice, elegant. recognizes a forma vmius and a forma 

Rods 1.5 to 1.7 by 2.5 to 5 microns; or ^agna, differentiated mainly by the size of 



longer just prior to cell division. Usually 
contain a large pseudovacuole (aerosome), 
leaving a rather thin protoplasmic sheath 
along the cell wall 



the individual rods. 

Habitat: Mud and stagnant water con- 
taining hj^drogen sulfide and exposed to 



Sulfur droplets generally quite small; light; sulfur springs, 
deposited exclusively in the thin proto- Illustrations: Winogradsky, ioc. ci<., Plate 

plasmic layer. Ill, fig. 13-17. 

Genus V. Thiothece Winogradsky, 1888. 

(Schwefelbacterien, Leipzig, 1888, 82.) 

Thi.o.the'ce Gr. noun thium sulfur; Gr. noun thece a box, chest; M.L. fem.n. Thiothece 
sulfur box. 

Sulfur purple bacteria which, in their growth characteristics, resemble the blue-green 
alga Aphanothece. Cells spherical to relatively long cylindrical-ellipsoidal, embedded in a 
gelatinous capsule of considerable dimensions. Following cell division the daughter cells 
continue to secrete mucus which causes the individual bacteria to remain clearly separated 
by an appreciable distance; the common capsule thus appears only loosely filled. The cells 
may become actively motile and separate themselves from the colony. Such swarmers 
closely resemble the cells of certain species of Chromatium. Contain bacteriochlorphyll 
and carotenoid pigments. Capable of photosynthesis in the presence of hydrogen sulfide, 
producing elemental sulfur as an intermediate oxidation product which is stored as sulfur 
globules inside the cells. 

The type species is Thiothece gelatinosa Winogradsky. 

1. Thiothece gelatinosa Winogradsky, in outermost layers of protoplasm and 
1888. (Schwefelbacterien, Leipzig, 1888. 82.) generally small. 

ge. la. ti. no'sa. L. part. adj. gre/aiMS frozen. Habitat: Mud and stagnant water con- 

stiffened; M.L. noun ffeZafznum gelatin, that taining hydrogen sulfide and exposed to 
which stiffens; M.L. adj. gelatinosus gelati- jj^^^. ^^^^^^ springs. 

Illustrations: Winogradsky, lac. cit., PI. 



nous. 

Cells 4 to 6 by 4 to 7 microns, spherical 
to cylindrical. Color of individual cells, 
faint, often grayish violet or even dirty Univ. Tokyo, Japan, 10, 1897, 170, PI. XIV 



III, fig. 9-12; Miyoshi, Jour. Coll. Sci., Imp. 

Univ. r 

yellowish. Sulfur globules usually deposited fig. 25. 



Genus VI. Thiocystis Winogradsky, 1888. 

(Schwefelbacterien, Leipzig, 1888, 60.) 

Thi.o.cys'tis. Gr. noun thium sulfur; Gr. noun cystis the bladder, a bag; M.L. fem.n. 
Thiocystis sulfur bag. 

Sulfur purple bacteria which form compact colonies, many of which may be loosely em- 
bedded in a common gelatinous capsule. Individual cells spherical to ovoid, often diplo- 
coccus-shaped. Colonies may emerge as more or less large units from out of the common 
capsule and break up afterwards, sometimes into single swarmers; or the aggregates may 
split up inside the original capsule and release small motile units or single swarmers. In 
pure cultures frequently develop as single cells and diplococci. Produce bacteriochlorophyll 



FAMILY I. THIORHODACEAE 43 

and carotenoid pigments, coloring the cell masses purplish to red. Capable of photosyn- 
thesis, in the presence of hydrogen sulfide, whereby elemental sulfur is formed as an inter- 
mediate oxidation product which is deposited as droplets inside the cells. 
The type species is Thiocystis violacea Winogradsky. 

Key to the species of genus Thiocystis. 

I. Individual cells more than 2 microns in width. 

1. Thiocystis violacea. 
II. Individual cells about 1 micron or less in width. 

2. Thiocystis rufa. 

1. Thiocystis violacea Winogradsky, taining hydrogen sulfide and exposed to 

1888. (Schwefelbacterien, Leipzig, 1888, 65.) light; sulfur springs. 

vi.o.la'ce.a. L. adj. violaceus violet- Illustrations: Zopf, Zur Morphologie der 

colored. Spaltpflanzen, Leipzig, 1882, PI. V, fig. 12; 

Cells about 2.5 to 5.5 microns in diam- Winogradsky, op. cit., 1888, 65, PI. II. Fig. 

eter, spherical to ovoid. Swarmers actively 1-7. 

motile by means of polar flagella. 

^ , . f, 1, . . , , 2. Ihiocystis rufa vVmogradsky, 1888. 

Colonies: Small, inside a common capsule, f lu + • t • • looo /=\ 



containing not over 30 cells. Several such 

colonies form loosely arranged aggregates, 

most characteristically composed of about _, , , n i , ^i. • ., , 

,- ^ _„ , . . • 1 IT., Color red, usually darker than in the type 

10 to 20 colonies in a single capsule. The re- . ' ,/ n «• j • l 



(Schwefelbacterien, Leipzig, 1888, 65.) 
ru'fa. L. adj. rujus red, reddish. 
Cells less than 1 micron in diameter. 



suit is a nearly spherical zoogloea. In small 

colonies, the cells appear as rather distinct ""oT bl*'"k 



species. When the cells are stuffed with 
sulfur globules, the aggregates appear al- 



tetrads; in larger colonies, the cells become 



The common gelatinous capsule usually 



somewhat compressed and the tetrad-like .obtains a far greater number of closely 

arrangement may be lost. p^^j^^^ individual colonies than is the case 

In pure cultures, the species often fails to Jq Thiocystis violacea. 

produce the characteristic capsules; the or- Habitat: Mud and stagnant water con- 

ganisms then occur as actively motile single taining hydrogen sulfide and exposed to 

cells or diplococci, with little or no slime light; sulfur springs, 

formation. No pseudocapsules are formed. Illustration: Winogradsky, loc. cit., PI. 

Habitat: Mud and stagnant water con- II, fig. 8. 

Genus VII. Lamprocystis Schroeter, 1886. 

(In part, Clathrocystis Cohn, Beitr. Biol. Pfl., /, Heft 3, 1875, 156; in part, Cohnia Winter, 
in Rabenhorst, Kryptogamen-Flora, 2 Aufl., 1884, 48; not Cohnia Kunth, Enumeratio plan- 
tarum, 5, 1850, 35; Schroeter, Die Pilze Schlesiens, in Cohn, Kryptogamen-Flora von 
Schle-sien, 3, 1, 1886, 151.) 

Lam.pro.cys'tis. Gr. adj. lamprus bright, brilliant; Or. noun cystis the bladder, a bag; 
M.L. fem.n. Lamprocystis a brilliant bag. 

Sulfur purple bacteria which form more or less large aggregates of cells enclosed in a 
common gelatinous capsule. Individual cells spherical to ovoid. Small aggregates closely 
resemble those of Thiocystis, even to the extent of the tetrad-like arrangement of cells in 
the small colonies. Behavior of the large aggregates during development appears to be 
different; the small individual cell groups or colonies do not emerge from the slime capsule 
until the initially relatively compact cell mass becomes broken up into smaller clusters, 
these eventually forming a somewhat net-like structure. This behavior has been ascribed 
to a change in the mode of cell division which at first appears to take place in three per- 
pendicular planes and later presumably changes to a division in only two directions. Cells 



44 ORDER I. PSEUDOMONADALES 

when free are motile by means of polar fiagella. In pure culture also this type rarely, if ever, 
produces large aggregates with the development here mentioned as characteristic for the 
genus (Bavendamm, Die farblosen und roten Schwefelbakterien, Pflanzenforschung, Heft 
2, 1924, 76). This, along with the other similarities, makes it doubtful whether future studies 
will result in the retention of the genera Lamprocijsiis and Thiocystis side by side. Produce 
bacteriochlorophyll and carotenoid pigments, coloring the cell masses purplish pink to red. 
Capable of photosynthesis in the presence of hj'drogen sulfide, storing elemental sulfur as 
globules inside the cells. 
The type species is Lamprocystis roseopersidna (Kiitzing) Schroeter. 

1. Lamprocystis roseopersicina (Kiitz- Winogradsky reports that the cells fre- 
ing, 1849) Schroeter, 1886. (Protococcus quently contain pseudovacuoles. 
roseopersicinus Kiitzing, Species Algarum, Habitat: Mud and stagnant water con- 
Leipzig, 1849, 196; Schroeter, in Cohn, taining hydrogen sulfide and exposed to 
Kryptogamen-Flora von Schlesien, 3, 1, light; sulfur springs. 
1886, 151.) Illustrations: Warming, Videnskab. 

ro.se.o.per.si.ci'na. L. adj. roseus rosy; Meddel. naturhistor. Foren., Kjobenhavn, 

Gr. noun persiCMS the peach (Persian apple); 1876, PI. VIII, fig. 3 g; Zopf, Z. Morphol. 

M.L. adj. roseopersicinus rosy peach (-col- d. Spaltpflanzen, Leipzig, 1882, PI. V, fig. 8, 

ored). 13; Winogradsky, Schwefelbacterien, Leip- 

Cells spherical to ovoid, 2 to 2.5 microns zig, 1888, PI. II, fig. 9-15; Bavendamm, Die 

in diameter, up to 5 microns long before cell farblosen und roten Schwefelbakterien, 

division. Motile by means of polar flagella. Jena, 1924, PI. II, fig. 3. 

Genus VIII. Amoebobacter Winogradsky , 18SS. 

(Schwefelbacterien, Leipzig, 1888, 71.) 

A.moe.bo.bac'ter. M.L. noun Amoeba a protozoan genus; Gr. noun amoebe change, trans- 
formation; M.L. noun bacter a rod; M.L. mas.n. Amoebobacter changeable rod. 

Sulfur purple bacteria, usually occurring in aggregates composed of many individuals 
without a characteristic common capsule. Slime formation can, nevertheless, be observed 
with very small colonies. With growth of the individual cells, the capsule bursts and the 
cell mass slowly moves out while the bacteria remain united. The colonies change their 
shape during growth and in response to environmental influences; the individual cells ap- 
pear motile and cause the movements of the entire colon3^ Winogradsky ascribes the co- 
herence of the cell masses to the existence of interconnecting protoplasmic filaments be- 
tween cells, but these have never been observed, and their occurrence is extremely doubtful. 
It is much more probable that the bacteria are held together by mucus, though not so much 
of the latter is produced as to form a clearly discernible capsule. Produce bacteriochloro- 
phyll and carotenoid pigments. Capable of photosynthesis in the presence of hydrogen 
sulfide, then storing sulfur as droplets inside the cells. 

The type species is Amoebobacter roseus Winogradsky. 

The characterizations of the genera Amoebobacter, Lamprocystis, Thiocystis, Thiocapsa 
and Thiothece are based upon the arrangement of individual bacteria in a common capsule. 
However, from Winogradsky's descriptions of Amoebobacter and from pure-culture studies 
with Thiocystis and Lamprocystis, the capsules have been shown to vary considerably, de- 
pending upon developmental stages and environmental conditions. Therefore it is quite 
possible that future investigations will show the desirability of restricting the number of 
genera. 

Key to the species of genus Amoebobacter. 

I. Cells spherical to ovoid, al)Out 2.5 to 3.5 microns in diameter and up to 6 microns in 
length prior to cell division. 

1. Amoebobacter roseus. 



FAMILY I. THIORHODACEAE 



45 



II. Cells distinctly rod-shaped, about 1.5 to 2 microns in width by 2 to 4 microns in length. 

2. Amoebobacter bacillosus. 
III. Cells spherical, quite small, about 0.5 to 1 micron in diameter. 

3. Amoebobacter granula. 



1. Anioebobacler roseus Winogradsky, 
1888. (Schwefelbacterien, Leipzig, 1888, 77.) 

ro'se.us. L. adj. roseus rosy. 

Cells spherical to ovoid, 2.5 to 3.5 microns 
in width and up to 6 microns in length. 
Motile. Often contain pseudovacuoles. Cell 
aggregates often form transitory hollow 
spheres or sacks with the bacteria occupy- 
ing the peripherj^ as a shallow layer. These 
are reminiscent of stages in the development 
of Lamprocystis. 

Habitat: Mud and stagnant water con- 
taining hj^drogen sulfide and exposed to 
light; sulfur springs. 

Illustrations: Winogradsky, loc. cit., PI. 
Ill, fig. 1-6. 

2. Amoebobacter bacillosus Winograd- 
sky, 1888. (Winogradsky, Schwefelbac- 
terien, Leipzig, 1888, 78; Thioderma roseum 
Miyoshi, Jour. Coll. Sci., Imp. Univ. 
Tokyo, Japan, 10, 1897, 158.) 

ba.cil.lo'sus. L. dim. noun bacillus a small 
staff or rod; M.L. adj. bacillosus full of 
(made up of) small rods. 

Cells rod-shaped, about 1.5 to 2 microns 
by 2 to 4 microns. Cells contain pseudo- 
vacuoles (aerosomes). Sulfur globules de- 
posited exclusively in peripheral proto- 
plasmic layer, usuallj' quite small. 

Mij'oshi's incomplete description of Thio- 
derma roseum (loc. cit.), type species of 
genus Thioderma, is sufficient to make prac- 



tically certain that it is identical with 
Amoebobacter bacillosus. The description of 
Thiodictyon elegans Winogradsky {op. cit., 
1888, 80) suggests that it cannot be distin- 
guished from this species. 

Habitat: Mud and stagnant water con- 
taining hydrogen sulfide and exposed to 
light; sulfur springs. 

Illustrations: Zopf, Z. Morphol. d. 
Spaltpfl., Leipzig, 1882, PI. V, fig. 26-27; 
Winogradsky, op. cit., 1888, PI. Ill, fig. 7. 

3. Amoebobacter granula Winograd- 
sky, 1888. (Schwefelbacterien, Leipzig, 
1888, 78.) 

gra'nu.la. L. dim. noun granulum a small 
grain; M.L. fem.n. granula a small grain. 

Cells spherical, small, about 0.5 to 1.0 
micron in diameter. Faint pigmentation; 
the sulfur inclusions give the cell masses a 
black appearance. Aggregates are apt to 
consist of closely-knit masses which are 
difficult to separate. 

When sulfur is stored, a single droplet 
usually fills most of the cell. Because of the 
high refractive index of this globule, it be- 
comes difficult if not impossible to make 
accurate observations of the cell shape. 

Habitat: Mud and stagnant water con- 
taining hj-drogen sulfide and exposed to 
light; sulfur springs. 

Illustration: Winogradsky, loc. cit., PI. 
Ill, fig. 8. 



Genus IX. Thiopolycoccus Winogradsky, 1888. 

(Schwefelbacterien, Leipzig, 1888, 79.) 

Thi.o.po.ly.coc'cus. Or. noun thium sulfur; Gr. adj. poly many; Gr. noun coccus a berry; 
M.L. noun coccus; M.L. mas.n. Thiopolycoccus with man}'- sulfur cocci. 

Sulfur purple bacteria which form dense aggregates of rather solid construction and ir- 
regular shape. The colonies appear, in contrast with those of Amoebobacter, non-motile and 
do not tend to form hollow zoogloeal structures by which they are differentiated from 
Lamprocystis. Cell masses held together by mucus which does not, however, appear as a 
regular capsule. Large clumps may fissure with the formation of irregular shreds and lobes 
which continue to break up into smaller groups of cells. Individual bacteria spherical, mo- 
tility not observed. Contain bacteriochlorophyll and carotenoid pigments, so that the 
aggregates, in accord with the dense packing with individual cells, appear distinctly red. 



46 ORDER I. PSEUDOMONADALES 

Capable of photosynthesis in the presence of hydrogen sulfide, when the cells store elemen- 
tal sulfur as droplets inside the cells. 
The type species is Thiopoly coccus ruber Winogi'adsky. 

1. Thiopolycoccus ruber Winogradsky, taining hydrogen sulfide and exposed to 

1888. (Schwefelbacterien, Leipzig, 1888, 79.) light; sulfur springs. 

ru'ber. L. adj. rwber red. Illustrations: Winogradsky, loc. cil., PI. 

Cells spherical, about 1.2 microns in di- IV, fig. 16-18; Issatchenko, Recherches sur 

ameter. No motility observed. les microbes de I'ocean glacial arctique. 

Habitat: Mud and stagnant water con- Petrograd, 1914, PI. II, fig. 7. 

Genus X. Thiospirillum Winogradsky, 1888. 

{Ophidomonas Ehrenberg, Die Infusionstierchen, Leipzig, 1838, 43; Winogradsky, Schwe- 
felbacterien, Leipzig, 1888, 104.) 

Thi.o.spi.ril'lum. Or. noun thium sulfur; M.L. dim.neut.n. Spirillum a bacterial genus; 
Gr. noun spira a spiral; M.L. neut.n. Thiospirillum suUur Spirillum. 

Sulfur purple bacteria, occurring singly as spirally wound cells, motile by means of polar 
flagella. Contain bacteriochlorophyll and carotenoid pigments, coloring the cells brownish 
to purplish red. Capable of photosynthesis in the presence of hydrogen sulfide, during which 
they produce and store, as an intermediate oxidation product, elemental sulfur in the form 
of droplets inside the cells. 

The differentiation of species in this group has been based exclusively on observations 
with material from natural collections and from laboratory mass cultures. The criteria 
used are the size and shape of the spirals and the color of the organisms. Not a single repre- 
sentative has so far been obtained and studied in pure culture, so that no information is 
available concerning the constancy or variability of these characteristics. It is likely, how- 
ever, that such properties may be greatly influenced by environmental factors. Hence, the 
following key and descriptions of species are apt to be modified when more extensive studies 
have been made. The published descriptions of some species make it seem probable that 
they should not even be incorporated in Thiospirillum. 

The type species is Thiospirillum jenense (Ehrenberg) Winogradsky. 

Key to the species of genus Thiospirillum. 

I. Width of cells 2.5 microns or more. 

A. Color of cells, especially in masses, yellowish brown to orange-brown. 

1. Thiospirillum jenense. 

B. Color of cells deep red or violet. 

1. Cells long, typical spirals; clearly red. 

2. Thiospirillum sanguineum. 

2. Cells short, slightly curved, vibrio-shaped; color purple to violet-red. 

3. Thiospirillum viokiceum. 
II. Width of cells less than 2.5 microns. 

A. Width of cells 1.5 to 2.5 microns. 

4. Thiospirillum rosenbergii. 

B. Width of cells about 1 micron. 

5. Thiospirillum rufum. 

1. Thiospirillum jenense (Ehrenberg, bacterien, Leipzig, 1888, 104; Thiospirillum 

1838) Winogradsky, 1888. (Ophidomonas cmssi<A« Hama, Jour. Sci. Hiroshima Univ., 

jenensis Ehrenberg, Die Infusionstierchen, Ser. B, Div. 2, Bot., 1, 1933, 157.) 

Leipzig, 1838, 44; Winogradsky, Schwefel- je.nen'se. M.L. adj. jenensis pertaining to 



FAMILY I. THIORHODACEAE 



47 



Jena; named for the city of Jena, Germany, 
where Ehrenberg discovered this organism. 

Cells 2.5 to 4.0 microns thick, cylindrical, 
sometimes pointed at the ends; coiled as 
spirals, generally 30 to 40 microns in length, 
but may be as long as 100 microns. Complete 
turns may measure from 15 to 40 microns 
with a wave depth of 3 to 7 microns. Polar 
flagellate. Tufted at both ends. Olive- 
brown, sepia-brown and reddish brown. 

This coloring appears to be the only rec- 
ognizable difference from Thiospirilhan san- 
(juineiim. Thiospirillum crassum Hama (loc. 
cit.), reported to be 3.7 to 4 by 12 to 40 
microns and yellowish brown in color, thus 
becomes indistinguishable from Thiospiril- 
lumjenense; the 80-microns-long Thiospiril- 
lum jenense forma maxima Szafer (Bull. 
Acad. Sci. Cracovie, S6r. B, 1910, 162) does 
not, at present, justify recognition as a 
special taxonomic entity. 

It is even doubtful whether the observed 
color difference between Thiospirillum 
jenense and Thiospirillum sanguineum con- 
stitutes a valid criterion for their mainte- 
nance as two distinct species (Buder, Jahrb. 
wiss. Bot., 56, 1915, 534; Bavendamm, Die 
farblosen und roten Schwefelbakterien, 
Pflanzenforschung, Heft 2, 1924, 131). 

Habitat: Mud and stagnant water con- 
taining hydrogen sulfide and exposed to 
light; more rarelj' in sulfur springs. 

Illustrations: Zettnow, Ztschr. f. Hyg., 
24, 1897, PI. II, fig. 49-52; Buder, op. cit., 
1915, 534, fig. 1; Szafer, op. cit., 1910, PI. IV, 
fig. 4; Hama, op. cit., 1933, PI. 18, fig. 1, 8a; 
PI. 19, fig. 1. 

2. Thiospirillum sanguineum (Ehren- 
berg, 1840) Winogradsky, 1888. (Ophido- 
monas sanguinea Ehrenberg, Verhandl. 
Akad. Wiss. Berlin, 1840, 201 ; Spirillum san- 
guineum Cohn, Beitr. Biol. Pfl., 1, Heft 3, 
1875, 169; Winogradsky, Schwefelbacterien, 
Leipzig, 1888, 104.) 

san.gui'ne.um. L. adj. sanguineus blood- 
colored, blood-red. 

Cells cylindrical, sometimes attenuated 
at ends, spirally coiled; 2.5 to 4.0 microns in 
width, commonly about 40 microns long 
with a range of from 10 to 100 microns. 
Size and shape of coils variable, complete 



turns measuring from 15 to 40 microns in 
length and from }4 to }{o of the length in 
width. Polar flagellate, usually tufted at 
both ends. Individual cells rose-red with a 
grayish hue, groups of cells deep red. Sulfur 
droplets numerous under appropriate con- 
ditions. 

Habitat: Mud and stagnant water con- 
taining hydrogen sulfide and exposed to 
light; rarely in sulfur springs. 

Illustrations: Cohn, op. cit., 1875, PI. VI, 
fig. 15; Warming, Vidensk. Meddel. natur- 
hist. Foren., Kjobenhavn, 1876, PI. VII, fig. 
8; Buder, Jahrb. wiss. Bot., 56, 1915, 534, 
fig. 2. 

3. Thiospirillum violaceum (Warming, 
1876) Winogradsky, 1888. {Spirillum vio- 
laceum Warming, Vidensk. Meddel. natur- 
hist. Foren., Kjobenhavn, 1876, 395; Wino- 
gradsky, Schwefelbacterien, Leipzig, 1888, 
104.) 

vi.o.la'ce.um. L. adj. violaceus violet- 
colored. 

Cells short and fat, 3 to 4 by 8 to 10 
microns, ends smoothly rounded. Slightly 
curved, bean- or vibrio-shaped. Onl}^ rarely 
are they twisted suggesting a spirillum. 
Polar flagellate. 

The shape of cell seems to fit the genus 
Chromatium rather than Thiospirillum, and 
Warming (op. cit., 1876, 395) emphasizes the 
resemblance to Chromatium okenii. 

Color: Bluish violet; this color may be re- 
lated to a scarcity of sulfur droplets in the 
cells. 

Habitat: Mud and stagnant water. 

Illustration: Warming, op. cit., 1876, PI. 
VII, fig. 3. 

4. Thiospirillum rosenbergii (Warm- 
ing, 1875) Winogradsky, 1888. (Spirillum 
rosenbergii Warming, Vidensk. Meddel. na- 
turhist. Foren., Kjobenhavn, 7, 1875, 346; 
Winogradsky, Schwefelbacterien, Leipzig, 
1888, 104.) 

ro.sen.ber'gi.i. M.L. gen. noun rosen&er^n 
of Rosenberg; named for Rosenberg, a 
Danish algologist. 

Cells 1.5 to 2.5 by 4 to 12 microns; coiled, 
with turns of about 6 to 7.5 microns in 
length and variable width up to 3 or 4 mi- 
crons. Color very dark, due to numerous 



48 ORDER I. PSEUDOMONADALES 

sulfur globules. Color of protoplasm not losen und roten Schwefelbakterien Jena, 
recorded. 1924, 132) or Huber-Pestalozzi (Die Bin- 
Habitat: Mud and stagnant water con- nengewasser, ^6, Heft 1, Das Phytoplankton 
taining hj'-drogen sulfide and exposed to des Siisswassers, Stuttgart, 1938, 304) that 
light. Probably widely distributed, but less the cells ever contain sulfur globules. Only 
frequently recorded as the organism is not the red color is emphasized. Consequently, 
so spectacular as the large Thiospirillum it is quite possible that this organism be- 
jenense and Thiospirillum sanguineum. longs in the genus Rhodospirillum. 

Illustration: Warming, op. cit., 1876, PI. Cells 1.0 by 8 to 18 microns; coiled to 

X, fig. 12. occupy 1}4 to 4 turns, the latter commonly 

4 microns wide by 4 microns long. These 

5. Thiospirillum rufum (Perty, 1852) dimensions agree with those of Rhodospiril- 

Migula, 1900. {Spirillum rufum Perty, Bern, lum ruhrum (Esmarch) Molisch, and it 

1852, 179; Migula, S3^st. d. Bakt. 2, 1900, seems probable that the two organisms are 

1050.) identical. 

ru'fum. L. adj. rujus red, reddish. Habitat: Found in red slime spots on the 

General characteristics presumably those side of a well. Mud and stagnant bodies of 

of the genus, although it does not appear water. 

either from Perty's description or from that Illustration: Migula, Syst. d. Bakt., 1, 

of Migula {loc. cit.), Bavendamm (Die farb- 1897, PI. Ill, fig. 7. 

Genus XI. Rhabdomonas Cohn, 1875. 

(Cohn, Beitr. Biol. Pfl., 1, Heft 3, 1875, 167; Rhahdochromalium Winogradsky, Schwefel- 
bacterien, Leipzig, 1888, 100.) 

Rhab.do.mo'nas. Or. noun rhabdus a rod; Or. noun monas a unit, monad; M.L. noun 
Manas a protozoan genus; M.L. fem.n. Rhabdomonas the rod monad. 

Sulfur purple bacteria, as a rule occurring singly in the form of rather irregular, long 
rods to filaments, exhibiting more or less pronounced swellings, or club and spindle shapes. 
Filamentous structures, sometimes with constrictions, giving the filament the appearance 
of a string of beads. These may be surrounded by a relatively inconspicuous slime capsule 
which can be rendered visible by India ink. The less distorted cell t3^pes are frequently 
motile b}^ means of polar flagella. Produce bacteriochlorophyll and carotenoid pigments, 
coloring the cells pinkish to purplish red. Capable of photosynthesis in the presence of 
hydrogen sulfide and then storing sulfur globules as an intermediate oxidation product in- 
side the cells. 

The status of this genus is doubtful. Winogradsky (loc. cit.) recognized the similarity of 
its members to species of Chromatium and the occurrence of many intermediate forms which 
make a sharp distinction between the two genera impossible. He preferred the designation 
of Rhabdochromatium as a sub-genus. Warming (Videnskab. Meddel. naturhist. Foren., 
Kjobenhavn, 1876, 320 ff.), Nadson (Bull. Jard. Imp(5r. Bot. St. P^tersb., 3, 1903, 116), van 
Niel (Arch. f. Mikrobiol., 8, 1931, 61) and Ellis (Sulphur Bacteria, London and New York, 
1932, 151) considered the species of Rhabdochroinatium as abnormal growth forms (involu- 
tion forms) of corresponding species of Chromatium, while Lauterborn (Verhandl. natur- 
histor.-medizin. Vereins, Heidelberg, N.F., 13, 1915, 424), Buder (Jahrb. wiss. Bot., 68, 
1919, 534) and Bavendamm (Die farblosen und roten Schwefelbakterien, Pflanzenforschung, 
Heft 2, 1924, 129) favor generic rank. 

The type species is Rhahdoinonas rosea Cohn. 

Key to the species of genus Khabdomonas. 

I. Cells not containing calcium carbonate inclusions in addition to sulfur globules. 
A. Cells more than 3 microns in width. 

1. Rhabdomonas rosea. 



FAMILY I. THIORHODACEAE 



49 



B. Cells less than 3 microns in width. 

2. Rhabdomonas gracilis. 

II. Cells containing calcium carbonate inclusions in addition to sulfur globules. 

3. Rhabdomonas linsbaueri. 



1. Rhabdomonas rosea Cohn, 1875. 
(Cohn, Beitr. Biol. Pfl., 1, Heft 3, 1875, 167; 
Beggiatoa roseo-persicina Zopf, Z. Morphol. 
d. Spaltpfianzen, Leipzig, 1882, 30; Rhabdo- 
chromatium roseiim Winogradsky, Schwefel- 
bacterien, Leipzig, 1888, 100; Rhabdochro- 
matium fusiforyne Winogradsky , ibid., 102.) 

ro'se.a. L. adj. roseus rosy, rose-red. 

Cells uneven in width and length, often 
swollen to spindle-shaped, sometimes tend- 
ing towards filamentous growth. The great- 
est width of a spindle-shaped or fusiform 
cell may be close to 10 microns; in the more 
filamentous structures it is usually around 
5 microns. The length varies between 10 and 
30 microns for single cells; filamentous 
forms, frequently showing bulges and con- 
strictions suggestive of compound struc- 
tures in which cell division has been incom- 
plete, may attain considerably greater 
lengths, up to 100 microns. The ends of 
spindle-shaped cells often taper to very fine 
points or attenuated fibers; also, filaments 
are generally thinner toward the extrem- 
ities. Single individuals and short filaments 
are motile by means of polar flagella, long 
filaments rarely motile. The ends of a fila- 
ment may become pinched off and swim 
away. 

Color rose-red; cells are usually filled with 
sulfur globules. 

There is no good reason for maintaining 
Rhabdomonas fusiformis (Rhabdochromatium 
fusiforme Winogradsky) as a separate 
species; the variations in size and shape 
bring this form well within the range of 
Rhabdomonas rosea. Present indications 
strongly suggest that the latter species 
should be regarded as a peculiar develop- 
mental form of Chromatium okenii. 

Habitat: Mud and stagnant water con- 
taining hydrogen sulfide and exposed to 
light; sulfur springs. 

Illustrations: Cohn, op. cit., 1875, PI. VI, 
fig. 14; Warming, Vidensk. Meddel. natur- 
histor. Foren., Kjobenhavn, 1876, PI. VII, 
fig. Ic-e; Zopf, op. cit., 1882, PI. V, fig. 2b; 



Winogradsky, op. cit., 1888, PI. IV, fig. 9-11, 
13-14. 

2. Rhabdomonas gracilis (Warming, 
1876) Bergey et al., 1923. {Monas gracilis 
Warming, Vidensk. Meddel. naturhist. 
Foren., Kjobenhavn, 1876, 331; Rhabdochro- 
matium minus Winogradsky, Schwefelbac- 
terien, Leipzig, 1888, 102; Rhodocapsa sus- 
pensa Molisch, Die Purpurbakterien, Jena, 
1907, 17; Bergey et al.. Manual, 1st ed., 
1923, 402.) 

gra'ci.lis. L. adj. gracilis thin, slender. 

Cells much smaller than those of Rhabdo- 
monas rosea and with less tendency to form 
fusiform cells. Usually filamentous, more or 
less cylindrical, often with constrictions, 
but found up to 60 microns in length. 
Shorter filaments motile. Polar flagellate. 
Slime formation may occur under special 
conditions. Rose-red. Sulfur globules. 
Probably an abnormal growth form of Chro- 
matium virosum. 

Habitat: Mud and stagnant water con- 
taining hydrogen sulfide and exposed to 
light; sulfur springs. 

Illustrations: Warming, op. cit., 1876, PI. 
VII, fig. 5; Winogradsky, op. cit., 1888, PI. 
IV, fig. 12; Molisch, op. cit., 1907, PI. II, fig. 
11-12. 

3. Rhabdomonas linsbaueri (Gickl- 
horn, 1921) van Niel, 1948. (Rhabdochroma- 
tium linsbaueri Gicklhorn, Ber. d. deut. bot. 
Ges., 39, 1921, 312; van Niel, in Manual, 6th 
ed., 1948, 855.) 

lins.bau'er.i. M.L. gen. noun linsbaueri of 
Linsbauer; named for K. Linsbauer, an 
Austrian botanist. 

Cells resemble those of Rhabdomonas rosea, 
irregular, rod-shaped, 3 to 5 microns wide, 
up to 30 microns in length. 

The characteristic feature of the species, 
and the chief means of differentiation, is the 
occurrence of calcium carbonate inclusions 
in addition to the sulfur globules in the cells. 
Whether this is strictly an environmentally 
conditioned characteristic, due to the 
photosynthetic development of the bacteria 



50 ORDER I. PSEUDOMONADALES 

in a medium rich in calcium ions, so that identity of this species with Rhabdomonas 

calcium carbonate is precipitated as the rosea would become evident, 

alkalinity increases, has not yet been estab- Source: From a pond near Graz, Austria, 

lished but seems possible. In that case the Habitat: Fresh water. 

Genus XII. Rhodothece Molisch, 1907. 

(Die Purpurbakterien, Jena, 1907, 19.) 

Rho.do.the'ce. Gr. noun rhodum the rose; Or. noun thece box (capsule); Rhodothece the 
rose capsule. 

Sulfur purple bacteria, occurring singly, not aggregated in families. Cells spherical, each 
surrounded by a rather wide capsule which is, however, rarely visible without special stain- 
ing. Motility not observed. Contain bacteriochlorophyll and carotenoid pigments, coloring 
the cells reddish. Capable of photosynthesis in the presence of hydrogen sulfide; the cells 
then store sulfur globules, arising as an intermediate oxidation product of the sulfide. 

In view of the experiences of Bavendamm and others that a number of representatives of 
the sulfur purple bacteria, characterized by typical colonial aggregates when found in 
nature, may develop as single cells in pure culture, it is quite conceivable that the genus 
Rhodothece is identical with some other genus, e.g., Thiopedia or Lamprocystis, and that 
these genera represent different growth forms induced by environmental conditions. 

The type species is Rhodothece pendens Molisch. 

1. Rhodothece pendens Molisch, 1907. nomena due to the pseudovacuoles and to 

(Die Purpurbakterien, Jena, 1907, 19.) the sulfur globules distort the cell shape 

pen'dens. L. part. adj. pendens hanging. under ordinary illumination so that bacteria 

Cells spherical, frequentlj^ occurring as appear as polygons rather than round cells, 

diplococci, occasionally as very short chains Usually 2 aerosomes and 2 sulfur globules 

or clumps of 3 to 5 individuals. 1.8 to 2.5 per cell. Color not observable in individual 

microns in diameter. Produce rather abun- bacteria. Cell groups are rose-red. Motility 

dant slime. Cells embedded in individual not observed. 

capsules which are rarely visible without Habitat: Mud and stagnant water con- 
staining (India ink). Characteristic is the taining hydrogen sulfide and exposed to 
regular occurrence of pseudovacuoles (aero- light. Not reported from sulfur springs, 
somes) which are supposed to keep the cells Illustrations: Molisch, Die Purpurbak- 
suspended in liquid media. Refractive phe- terien, Jena, 1907, PI. II, fig. 13-14. 

Genus XIII. Chromatium Perty, 1852. 

(Zur Kenntniss kleinster Lebensformen, Bern, 1852, 174.) 

Chro.ma'ti.um. Gr. noun chromatium color, paint. 

Cells occur singly, more or less ovoid, bean- or vibrio-shaped or short rods. The last- 
mentioned are often thick-cj'lindrical with rounded ends. Motile by means of polar flagella. 
Contain bacteriochlorophyll and carotenoid pigments, coloring the cells various shades of 
red. Capable of photosynthesis in the presence of hydrogen sulfide and storing elemental 
sulfur as an incomplete oxidation product in the form of globules inside the cells. 

At present the genus contains twelve described species. Differentiation of these species 
has, in the past, been based almost entirely upon size and shape of individual cells, often 
with complete disregard for the variability of these criteria. The unsatisfactory and arbi- 
trary nature of such a classification has occasionallj^ been pointed out, and with much 
justification. Winogradsky (Schwefelbacterien, Leipzig, 1888, 98) mentions the many transi- 
tional stagfes that can be observed between Chromatium okenii and Chromatium weissei; 
Strzeszewski (Bullet. Acad. Sci., Cracovie, Ser. B, 1913, 321) holds that it is impossible to 
distinguish, on the basis of sizes or otherwise, between Chromatium weissei and Chromatium 
minus. Such contentions, derived from observations on material from natural collections or 



FAMILY I. THIORHODACEAE 



51 



crude cultures, have been greatly strengthened by studies with pure cultures of species of 
Chromatium. Thus van Niel (Arch. f. Mikrobiol., 3, 1931, 59) reported variations in width 
from 1 to 4 microns, and in length from 2 to 10 microns or even up to 50 microns; Manten 
(Antonie van Leeuwenhoek, 8, 1942, 164 S.) found size differences of 1 to 14 microns with a 
pure culture of an organism that he identified as Chromatium okenii. Often the differences 
in size of a pure culture can be related to special environmental conditions. On account of 
such results a designation of species on the basis of size relations alone is manifest)}^ un- 
satisfactory. Moreover, the available data do not suggest that differences in shape, color or 
arrangement of sulfur globules can be used more effectively. Lack of adequate experimental 
results with a sufficiently large number and variety of pure cultures prevents a more rational 
classification at present. 

The previously proposed species have been listed below with their respective character- 
istics and arranged as far as possible in the order of decreasing width. 

Two Chromatium species have been described as containing inclusions of calcium carbon- 
ate in addition to sulfur globules. As in the case of Rhabdomonas linsbaueri, it is not known 
w'hether this feature may be a direct consequence of the calcium ion content and pH of the 
environment and thus fail to have taxonomic significance. 

The type species is Chromatium okenii Perty. 



1. Chromatium gobii Issatchenko, 1914. 
(Recherches sur les microbes de I'oc^an 
glacial arctique, Petrograd, 1914, 253.) 

go'bi.i. M.L. gen.noun gobii of Gobi; 
named for Prof. X. Gobi. 

Cells 10 microns by 20 to 25 microns. 

Source: From sea water of the Arctic 
Ocean. 

Habitat: Presumably ubiquitous in the 
colder portions of the Ocean at least. 

Illustration: Issatchenko, loc. cit., PI. II, 
fig. 12. 

2. Chromatium warmingii (Cohn, 1875) 
Migula, 1900. (Monas warmingii Cohn, 
Beitr. Biol. Pfl., i. Heft 3, 1875, 167; Migula, 
Syst. d. Bakt., 2, 1900, 1048.) 

war.min'gi.i. Named for Eugene Warm- 
ing, a Danish botanist; M.L. gen.noun 
warmingii of Warming. 

Cells 8 by 15 to 20 microns, also smaller 
(Cohn). 

Illustration: Cohn, op. cit., 1875. PI. VI, 
fig. 11. 

3. Chromatium linsbaueri Gicklhorn, 
1921. (Ber. d. deut. botan. Ges., 39, 1921, 
312.) 

lins.bau'er.i. Named for K. Linsbauer, an 
Austrian botanist; M.L. gen.noun linsbaueri 
of Linsbauer. 

Cells 6 by up to 15 microns (Gickl- 
horn) ; 6 to 8 microns in width (Ellis, Sul- 
phur Bacteria, London and New York, 1932, 



147) . Special characteristic is the occurrence 
of calcium carbonate inclusions. Otherwise 
resembles Chromatium okenii. 

Source: From a pool in the Stiftingtal, 
near Graz, Austria. 

Habitat: Fresh water. 

Illustrations: Gicklhorn, op. cit., 1921, 
314, fig. 1; Ellis, op. cit., 1932, 148, fig. 31. 

4. Chromatium okenii (Ehrenberg, 
1838) Perty, 1852. {Monas okenii Ehrenberg, 
Infusionsthierchen, Leipzig, 1838; Perty, 
Zur Kenntniss kleinster Lebensformen, 
Bern, 1852, 174.) This is the type species of 
genus Chromatium. 

o.ke'ni.i. Named for L. Oken, a German 
naturalist; M.L. gen.noun okenii of Oken. 

Cells 5.6 to 6.3 by 7.5 to 15 microns 
(Cohn) ; minimum width 4.5 microns (Issat- 
chenko, Borodin Jubilee Vol., 1929?, 8); 
with many transitions to Chromatium weis- 
sei (Winogradsky, Schwefelbacterien, Leip- 
zig, 1888, 92). Also: 3.5 by 8 to 12 microns 
and varj'ing in size from 1 to 15 microns 
(Manten, Antonie van Leeuwenhoek, 8, 1942, 
164). 

Illustrations: Cohn, Beitr. Biol. Pfl., 1, 
Heft 3, 1875, PI. VI, fig. 12; Winogradsky, 
op. cit., 1888, PI. IV, fig. 3-4; Issatchenko, 
Recherches sur les microbes de I'ocean 
glacial arctique, Petrograd, 1914, PI. II, 
fig. 9. 

5. Chromatium weissei Perty, 1852. 



oz 



ORDER I. PSEUDOMONADALES 



(Zur Kenntniss kleinster Lebensformen, 
Bern, 1852, 174.) 

weis'se.i. Named for J. F. Weisse, a zoolo- 
gist; M.L. gen. noun weissei of Weisse. 

Cells 4.2 by 5.7 to 11.5 microns (Perty); 
also 3 to 4 by 7 to 9 microns (Issatchenko, 
Borodin Jubilee Volume, 1929?, 8); transi- 
tions to Chromatium okenii (Winogradsky, 
Schwefelbacterien, Leipzig, 1888, 92); 
transitions to Chromatium minus (Strzes- 
zewski, Bull. Acad. Sci., Cracovie, Ser. B, 
1913, 321). 

Illustrations: Winogradsky, op. cit., 1888, 
PI. IV, fig. 1-2, Miyoshi, Jour. Coll. Sci., 
Imp. Univ. Tokyo, Japan, 10, 1897, PI. 
XIV, fig. 15. 

6. Chromatium cuculliferum Gickl- 
horn, 1920. (Cent, f . Bakt., II Abt., 50, 1920, 
419.) 

cu.cul.li'fe.rum. L. noun cucullus hood, 
cap; L. V. few to bear; M.L. adj. cucullifer 
cap-bearing. 

Cells 4 by 6 to 8 microns (Gicklhorn) ; 
according to Bavendamm (Schwefelbak- 
terien, Jena, 1924, 127), identical with 
Chromatium warmingii forma minus. Gickl- 
horn claims this organism to be colorless, 
which appears very doubtful. 

Source: From the pond in the Annen 
Castle Park, Graz, Austria. 

Habitat: Fresh-water ponds. 

Illustration: Gicklhorn, op. cit., 1920, 419, 
fig. 2. 

7. Chromatium minus Winogradsky, 
1888. (Schwefelbacterien, Leipzig, 1888, 99.) 

mi'nus. L. comp.adj. minor (neut. minus) 
less, smaller. 

Cells 3 by 3.5 to 7 microns (Winograd- 
sky) ; also 1.7 to 3 microns in width and up to 
8.5 microns in length (Issatchenko, Borodin 
Jubilee Volume, 1929?, 9); all transitions to 
Chromatium weissei from which it cannot be 
distinguished (Strzeszewski, Bull. Acad. 
Sci., Cracovie, Ser. B, 1913, 321). 

Illustrations: Winogradsky, op. cit., 1888, 
PI. IV, fig. 5; Miyoshi, Jour. Coll. Sci., Imp. 
Univ., Tokyo, Japan, 10, 1897, PI. XIV, fig. 
16; Issatchenko, Recherches sur les microbes 
de I'ocean glacial arctique, Petrograd, 1914, 
PI. II, fig. 10-11. 



8. Chromatium vinosum (Ehrenberg, 
1838). Winogradsky, 1888. {Monas vinosa 
Ehrenberg, Die Infusionstierchen, Leipzig, 
1838, 11; Winogradsky, Schwefelbacterien, 
Leipzig, 1888, 99.) 

vi.no'sum. L. adj. vinosus full of wine. 

Cells 2 by 2.5 to 5 microns; also 1.4 to 3 by 
1.5 to 5 microns (Jimbo, Botan. Magaz. 
Tokyo, 51, 1937, 872); 1.7 to 2 by 2 to 9 
microns (Issatchenko, Borodin Jubilee 
Volume, 1929?, 9) ; or 1 to 1.3 microns by 2.5 
to 3 microns (Schrammeck, Beitr. Biol. d. 
Pflanzen, 22, 1935, 317). Jimbo considers 
Thioderma roseum Miyoshi to be identical 
with Chromatium vinosum. 

Illustrations: Winogradsky, op. cit., 1888, 
PI. IV, 6-7; Miyoshi, Jour. Coll. Sci., Imp. 
Univ. Tokyo, Japan, 10, 1897, PI. XIV, fig. 
17; Nadson, Bull. Jard. Imp. Botan., St. 
Petersbourg, 12, 1912, PI. Ill, fig. 1-2. 

9. Chromatium violaceum Perty, 1852. 
(Zur Kenntniss kleinster Lebensformen, 
Bern, 1852, 174.) 

vi.o.la'ce.um. L. adj. violaceus violet- 
colored. 

Cells about 2 by 2 to 3 microns. Accord- 
ing to Cohn (Beitr. Biol. Pfl., 1, Heft 3, 
1875, 166), probably identical with Chro- 
matium vinosum. Apparently includes var- 
ious sizes. 

10. Chromatium molischii (Bersa, 
1926) van Niel, 1948. {Pseudomonas molischii 
Bersa, Planta, 2, 1926, 375; van Niel, in 
Manual, 6th ed., 1948, 858.) 

mo.li'schi.i. Named for H. Molisch, an 
Austrian botanist; M.L. gen. noun molischii 
of Molisch. 

Cells about 2 by 2.5 to 8 microns. Sup- 
posedly contain calcium carbonate as in- 
clusions. 

Illustration: Bersa, op. cit., 1926, 376, fig. 
3. 

11. Chromatium gracile Strzeszewski, 
1913. (Bull. Acad. Sci., Cracovie, Ser. B, 
1913, 321.) 

gra'ci.le. L. adj. gracilis thin, slender. 

Cells 1 to 1.3 by 2 to 6 microns; also to 1.5 
microns in width (Issatchenko, Etudes mi- 
crobiologiques des Lacs de Boue, Leningrad, 
1927, 114). 

Illustration: Strzeszewski, op. cit., 1913, 



FAMILY I. THIORHODACEAE 53 

PI. XXXIX, fig. 1-2; Tokuda, Botau. from 0.5 to 0.7 by 0.6 to 1 micron (Issat- 

Magaz., Tokyo, 50, 1936, 339, fig. 1-23. chenko, Recherches sur les microbes de 

I'ocean glacial arctique, Petrograd, 1914, 

12. Chroniatium miniitissiniuin Wino- 253), and 1 to 3 by 2 to 5 microns (Issat- 

gradskjr, 1888. (Schwefelbacterien, Leipzig, chenko, Borodin Jubilee Volume, 1929?, 9). 

1888, 100.) Illustrations : Winogradsky, op. cit., 1888, 

mi.nu.tis'si.mum. L. sup. adj. minutissi- PI. IV, fig. 8; Miyoshi, Jour. Coll. Sci., Imp. 

mtfs very small. Univ., Tokyo, Japan, 10, 1897, PI. XIV, 

Cells about 1 to 1.2 by 2 microns. Also fig. 18. 



FAMILY II. ATHIORHODACEAE MOLISCH, 1907. 

(Die Purpurbakterien, Jena, 1907, 28.) 

A.thi.o.rho.da'ce.ae. Or. pref. a without; Gr. noun ihium sulfur; Gr. noun rhodum the 
rose; -aceae ending to denote a family; M.L. fem.pl.n. Athiorhodaceae (probably intended 
to mean) the family of the non-sulfur red bacteria. 

Unicellular bacteria, of relatively small size, occurring as spheres, short rods, vibrios, 
long rods and spirals. Motility is due to the presence of polar flagella. Gram-negative. They 
produce a pigment sj^stem composed of bacteriochlorophyll and one or more carotenoids, 
coloring the cells yellowish brown, olive-brown, dark brown or various shades of red. Color 
usually not observable with single cells but only with cell masses. Generally microaero- 
philic, although many representatives may grow at full atmospheric oxygen tension. Capa- 
ble of development under strictly anaerobic conditions, but only in illuminated cultures by 
virtue of a photosynthetic metabolism. The latter is dependent upon the presence of ex- 
traneous hydrogen donors, such as alcohols, fatty acids, hydroxy- and keto-acids, and does 
not proceed with the evolution of molecular oxygen. Those members which can grow in the 
presence of air can also be cultivated in darkness, but only under aerobic conditions. 

The growth requirements of some of the species in this family have been reported by 
Hutner (Arch. Biochem., 3, 1944, 439; Jour. Bact., 52, 1946, 217; Jour. Gen. Microbiol., 4, 
1950, 286) ; his findings are incorporated in the descriptions which follow. 

Key to the genera of family Athiorhodaceae. 

I. Cells rod-shaped or spherical, not spiral-shaped. 

Genus I. Rhodopseudomonas , p. 53. 
II. Cells spiral-shaped. 

Genus II. Rhodospirillum, p. 58. 

Genus I. Rhodopseudomonas Kluyver and van Niel, 19S7, emend, van Niel, 1944- 

(Includes Rhodobacillus Molisch, Die Purpurbakterien, Jena, 1907, 14; Rhodobacterium 
Molisch, ibid., 16; Rhodococcus Molisch, ibid., 20; Rhodovibrio Molisch, ibid., 21; Rhodocystis 
Molisch, ibid., 22; Rhodonostoc Molisch, ibid., 23; Rhodosphaera Buchanan, Jour. Bact., S, 
1918, 472; Rhodorhagus (sic) Bergey et al.. Manual, 2nd ed., 1925, 414; Rhodomonas Kluyver 
and van Niel, Zent. f. Bakt., II Abt., 94, 1936, 397; not Rhodomonas Orla-Jensen, Cent. f. 
Bakt., II Abt., 22, 1909, 331 ; Kluyver and van Niel, in Czurda and Maresch, Arch, f . Mikro- 
biol., 8, 1937, 119; Rhodorrhagus Bergey et al.. Manual, 5th ed., 1939, 905; van Niel, Bact. 
Rev., 8, 1944, 86.) 

Rho.do.pseu.do.mo'nas. Gr. noun rhodum the rose; Gr. adj. pseudes false; Gr. noun 
monas monad, unit; M.L. fem.n. Pseudotnonas a bacterial genus; M.L. fem.n. Rhodopseudo- 
monas the rose Pseudomonas. 

Spherical and rod-shaped bacteria, motile by means of polar flagella. Gram -negative. 



54 ORDER I. PSEUDOMONADALES 

Contain bacteriochlorophjdl which enables them to carry out a photosynthetic metabolism. 
The latter is dependent upon the presence of extraneous oxidizable substances and proceeds 
without the evolution of molecular oxygen. Though some members can oxidize inorganic 
substrates, none appears to be strictly autotrophic due to the need for special organic growth 
factors. Produce accessory pigments causing the cultures, especially when kept in light, to 
appear in various shades of brownish yellow to deep red. 
The type species is Rhodopsendornonas palnstris (Molisch) van Niel. 

Keys to the species of genus Rhodopseudomonas. 

I. Based upon morphological characters. 

A. Cells clearly rod-shaped in all media. 

1. Cells short, somewhat curved, to long branched rods, size of j'oung and short 
cells 0.6 to 0.8 by 1.2 to 2 microns; in older cultures up to 10 microns long; do 
not form slime; liquid cultures, when young, or after shaking, evenly turbid. 
Color red to dark brown-red. 

1. Rhodopseudomonas palustris. 

2. Cells slender rods, 0.5 by 1.2 microns, usually clumped together in extensive 
slime masses. Cultures pale brown to peach-colored. 

2. Rhodopseudomonas gelatinosa. 

B. Cells more or less spherical in media at pH below 7. 

1. In media at pH about 7 clearly rod-shaped, 1 by 1 to 2.5 microns. Chains of cells 
frequent and in characteristic zigzag arrangement. 

3. Rhodopseudomonas capsulaia. 

2. In media at pH above 7 cells still predominantly spherical, 0.7 to 4 microns in 
diameter. Mostly single, little tendency to chain formation. 

4. Rhodopsendomonas spheroides. 
II. Based chiefly on physiological properties. 

A. Gelatin liquefied. 

2. Rhodopseudomonas gelatinosa. 

B. Gelatin not liquefied. 

1. Does not produce mucus in media at pH above 8. Color the same under aerobic 
and anaerobic conditions of growth. 

1. Rhodopseudomonas palustris. 

2. Produce mucus in media at pH above 8. Color brow^n in anaerobic, red in aerobic 
culture. 

a. Develops readily in media with 0.2 per cent propionate as the chief oxidation 
substrate. Mucus production marked at pH above 8, but very limited be- 
tween 7 and 8. 

3. Rhodopseudomonas capsulata. 

aa. Does not develop in media with 0.2 per cent propionate as the main oxida- 
tion substrate. Slime formation extensive at pH above 7. 

4. Rhodopseudomonas spheroides. 
III. Based principally upon biochemical characters. 

A. Thiosulfate used as main oxidation substrate. 

1. Rhodopseudomonas palustris. 

B. Thiosulfate not used. 

1. Propionate (0.2 per cent) used. 

3. Rhodopseudomonas capsulata. 

2. Propionate not used. 

a. Mannitol and sorbitol (0.2 per cent) used. 

4. Rhodopseudomonas spheroides. 
aa. Mannitol and sorbitol not used. 

2. Rhodopseudomonas gelatinosa. 



FAMILY II. ATHIORHODACEAE 



55 



1. Rhodopseudonionas palustris (Mo- 
lisch, 1907) van Niel, 194-4. [Rhodobacillus 
palustris ]Molisch, Rhodobacterium capsula- 
tum Molisch and Rhodovibrio parvus Mo- 
lisch, Die Purpurbakterien, Jena, 1907, 14, 
18 and 21 ; van Niel, Bact. Rev., 8, 1944, 89.) 

pa.lu.s'tris. L. adj. paluster marshy, 
swampy. 

Cells usually distinct!}^ rod-shaped, 
though in young cultures very short, lightly 
curved rods may often predominate. Size 
variable, even for the same strain, and 
strongly influenced by age of culture and 
composition of medium. Rather consistently 
short cells in young cultures in yeast ex- 
tract, especially when incubated anaerobi- 
cally in the light or in anaerobic cultures 
with substrates, such as malonate, which 
permit only a slow and scant develop- 
ment. Dimensions in such cultures 0.6 to 0.8 
by 1.2 to 2 microns. More often, especially 
in older cultures, cells are much longer, up 
to 10 microns. Highly characteristic is the 
pronounced tendency to the formation of 
irregularly shaped, bent and crooked long 
rods, occasionally swollen at one or both 
e.xtremities, and frequently suggesting 
branching. Such cells usually form clusters 
reminiscent of Corynebacterium and Myco- 
bacterium cultures. 

Cells in young cultures actively motile by 
means of polar flagella; irregular and long 
cells as a rule non -motile. Gram-negative. 

Growth in liquid media never mucoid; 
sediment in older cultures homogeneous and 
smooth, readily redispersible. 

Color varies considerably, depending upon 
the medium, and especially in anaero- 
bic illuminated cultures. Where develop- 
ment is slight (as in malonate, thiosulfate 
and, usually, glycerol media), the color is a 
light pink; in media containing fatty acids, 
more nearly dark reddish brown. Color due 
to bacteriochlorophyll and a number of dif- 
ferent carotenoid pigments; most strains 
produce, in addition, a water-soluble, non- 
carotenoid, bluish red pigment which dif- 
fuses into the culture medium. 

In yeast extract cultures growth is pos- 
sible over the range pH 6 to 8.5. With cer- 
tain substrates, especially fatty acids, the 
combined effect of low pH and a substrate 
concentration of 0.1 to 0.2 per cent may pre- 



vent growth. No characteristic odors save 
that old cultures may develop a distinct 
ionone-like fragrance. Gelatin is not lique- 
fied; leucine is generally utilized as a sub- 
strate. 

Most strains are able to grow on the sur- 
face of agar plates or slants ; a few, especially 
when first isolated, appear more sensitive to 
oxygen and develop only in stabs in which 
the upper region may remain free of growth. 
Generally such strains can be adapted to 
grow at full atmospheric oxygen tension. 

Most fatty acids and hydroxy acids are 
adequate oxidation substrates. All cultures 
can grow at the expense of thiosulfate and 
produce rapid and profuse growth in glu- 
tarate and ethanol media. No development 
in media containing, as the chief oxidation 
substrate, 0.2 per cent sorbitol, glucose or 
mannose, even though these substances are 
not inhibitory. Molecular hydrogen can be 
oxidized. 

All cultures can develop anaerobically in 
illuminated cultures by photosj^nthesis. 

p-amino-benzoic acid is required for 
growth (Hutner). 

Optimum temperature generally rather 
high, good development being possible up 
to 37° C. However, certain strains exhibit a 
lower optimum temperature. 

Distinctive characters : Morphological 
resemblance to species of Mycobacterium in 
old cultures, ability to grow with thiosulfate 
as the chief oxidizable substrate, and failure 
to develop in media which contain carbohy- 
drates or sugar alcohols in a concentration 
of 0.2 per cent as the main oxidizable com- 
pounds. 

Habitat: Regularly found in mud and 
stagnant bodies of water. 

Illustrations: Molisch, op. cit., 1907, 
Plate I, fig. 1, 2; Plate II, fig. 10; van Niel, 
op. cit., 1944, fig. 1-3, p. 18, and fig. 18-26, 
p. 90. 

2. Rhodopseudomonas gelatinosa (Mo- 
lisch, 1907) van Niel, 1944. (Rhodocystis 
gelatinosa Molisch, Die Purpurbakterien, 
Jena, 1907, 22; van Niel, Bact. Rev., 8, 1944, 

98.) 

ge.la.ti.no'sa. L. part. adj. gclatus frozen, 
stiffened; M.L. gelatinum gelatin, that which 



56 



ORDER I. PSEUDOMONADALES 



stiffens; M.L. adj. gelatinosus full of gelatin, 
gelatinous. 

Cells in young cultures short and small 
rods, approximately 0.5 by 1 to 2 microns. 
In old cultures much longer, up to 15 mi- 
crons, and then irregularly curved rods, 
often swollen and gnarled in places up to 1 
micron in width. In this stage the cells bear 
some resemblance to those found in old cul- 
tures of Rhodopseudomonas palustris, but 
the characteristic Mycobacterium-Yike clus- 
ters of the latter are absent. Single cells in- 
frequent due to a copious mucus produc- 
tion in all media which causes the cells to 
clump together. While young cells are ac- 
tively motile by means of polar flagella, 
motility is often difficult to ascertain as a 
result of the pronounced tendency to con- 
glomerate; the individuals in the clumps 
appear to be non-motile. Gram-negative. 
Gelatin is liquefied; of the single amino acids 
alanine, asparagine, aspartic and glutamic 
acids appear generally satisfactory sub- 
strates. 

Color quite distinctive in most anaerobic 
cultures as a pale, delicate, pinkish shade, 
rather peach-colored. Only in the presence 
of rather high concentrations of yeast ex- 
tract (when a much heavier growth is ob- 
tained than with low concentrations supple- 
mented with 0.2 per cent of various single 
oxidation substrates) do the slimy cell 
masses appear a dirty, faded brown. Color 
is due to bacteriochlorophyll and carotenoid 
pigments. Occasionally a water-soluble, 
non-carotenoid, bluish red pigment is 
produced which diffuses into the culture 
medium. 

In j^east extract, growth occurs over a pH 
range extending from at least 6.0 to 8.5. 

Cultures produce a characteristic acrid 
odor. 

More sensitive to fatty acids than are 
other species of Rhodopseudomonas; with 
0.2 per cent propionate no growth occurs. 
The best single oxidizable substrates appear 
to be ethanol, glucose, fructose and man- 
nose, as well as a variety of amino acids. 
Citrate also permits good growth; not, on 
the other hand, glycerol, mannitol, sorbitol 
or tartrate in the usual concentration of 
0.2 per cent. 



Thiosulfate is not oxidized; behavior 
towards molecular hydrogen unknown. 

More pronouncedly microaerophilic than 
the other Rhodopseudomonas species; most 
cultures cannot develop on aerobically in- 
cubated slants or agar plates. 

Capable of strictly anaerobic development 
in illuminated cultures by virtue of a photo- 
synthetic metabolism. 

Thiamin plus biotin is required for growth 
(Hutner). 

Temperature relations so far unknown. 

Distinctive characters: The small size of 
the individual cells and the pronounced 
clumping which causes the cultures to be 
exceptionally stringy; the unusual color of 
the cell masses; the ability to liquefy gela- 
tin, to utilize citrate and a number of amino 
acids. Correlated with these is the failure to 
grow in media with 0.2 per cent propionate, 
tartrate and glycerol. 

Habitat: Regularly' present in stagnant 
bodies of water and in mud. 

Illustrations : Molisch, op. cit., 1907, Plate 
I, fig. 8; van Niel, op. cit., 1944, fig. 55-60, p. 
99; fig. 61-66, p. 100. 

3. Rhodopseudomonas capsulata (Mo- 
lisch, 1907) van Niel, 1944. {Rhodonostoc 
capsulatum Molisch, Die Purpurbakterien, 
Jena, 1907, 23; Rhodopseudomonas capsulatus 
(sic) van Niel, Pact. Rev., S, 1944, 92.) 

cap.su.la'ta. L. dim. noun capsula a small 
chest, capsule; M.L. adj. capsulatus capsu- 
lated. 

Depending upon the pH of the medium, 
cells nearly spherical, or as distinct rods, 
often devoid of motility. Motility due 
to polar flagella. The spherical cells are 
found in media with a pH below 7; thej' are 
usually arranged in chains resembling strep- 
tococci. Rod-shaped cells are characteristic 
for media with pH above 7; the higher the 
pH, the longer the rods. Individual cells 
slightly less than 1 micron wide, although 
attenuated rods (about 0.5 micron in width) 
are frequent at pH above 8, and slightly 
swollen cells (to 1.2 microns) are found in 
media containing sugars. Length varies from 
1 to 6 microns; most common dimensions in 
approximately neutral media, 2 to 2.5 mi- 
crons. At pH above 8, abnormal growth in 



FAMILY II. ATHIORHODACEAE 



57 



the form of irregular filaments. Outstand- 
ingly characteristic is the zigzag arrange- 
ment of the cells in chains. Gram-negative. 

Cultures in media of pH 8 or above are 
distinctly mucoid. 

Color: Anaerobic cultures develop with a 
brown color, the shade ranging from a light 
3'ellowish l^rown to a deep mahogany- 
brown. When grown in the presence of oxy- 
gen, the cultures are dark red. Even the pig- 
mentation of the brown-colored organisms 
from an anaerobic culture can be changed 
into a distinct red by shaking a suspension 
with air for some hours; light enhances the 
rate of this color change. Color due to bac- 
teriochlorophyll and carotenoid pigments. 
No diffusible water-soluble pigment is pro- 
duced. 

Growth possible over a pH range from at 
least 6 to 8.5, morphology becoming abnor- 
mal in the alkaline media. 

Most cultures are odorless, although occa- 
sionally a faint peach-like odor can be de- 
tected. 

Growth is not inhibited by the presence of 
oxygen, although the pigmentation is 
thereby affected. 

Fatty acids and most substituted acids 
are satisfactory substrates. Rapid and 
abundant growth with propionate at a 
concentration of 0.2 per cent. At this same 
concentration glutaric acid leads, at best, to 
very meager cultures, while tartrate, citrate 
and gluconate fail to induce growth, as do 
also ethanol, glycerol, mannitol and sorbi- 
tol. In media with 0.2 per cent glucose or 
fructose good growth is obtained. No growth 
with mannose. Thiosulfate is not, but 
molecular hydrogen can be, oxidized by this 
species. 

Gelatin is not liquefied; of the amino 
acids, alanine and glutamic acid are satis- 
factory substrates while leucine is not uti- 
lized. 

Distinctive characters: Cell shape and 
arrangement in chains; brown color of 
anaerobic, red pigmentation of aerobic cul- 
tures; ability to grow in media with 0.2 per 
cent propionate, glucose, fructose, alanine 
and glutamic acid; failure to develop with 
leucine, as well as with ethanol, glycerol, 
mannitol and sorbitol in the above-men- 
tioned concentration. 



All cultures can develop anaerobically in 
illuminated cultures by a photosynthetic 
metabolism. 

Thiamin is required for growth; u few 
strains require biotin and nicotinic acid in 
addition (Hutrier). 

Optimum temperature distinctly lower 
than for Rhodopseudomonas palustris, and, 
as a rule, around 25° C. 

Habitat: Regularly found in stagnant 
bodies of water and in mud. 

Illustrations: Molisch, op. cit., 1907, 
Plate II, fig. 9; van Niel, op. cit., 1944, fig. 
4-6, p. 19; fig. 27-32, p. 92; and fig. 33-38, p. 
93. 

4. RhodopseudonionaH spheroides van 

Niel, 1944. {Rhodococcus capsulatus Molisch, 
Die Purpurbakterien, Jena, 1907, 20; Rhodo- 
coccus minor Molisch, ibid., 21; van Niel, 
Bact. Rev., 8, 1944, 95.) 

sphe.ro. i'des or sphe.roi'des. Gr. adj. 
sphaeroides globular. 

Cells generally single, nearly spherical, 
diameter without slime capsule variable, de- 
pending upon medium, ranging from 0.7 to 
4 microns. In young cultures actively motile 
by means of polar flagella; motility soon 
ceases in media which are or become alka- 
line. Copious slime production in media at 
pH above 7. In strongly alkaline cultures 
abnormal cell-shapes occur in the form of 
irregular, swollen and distorted rods, often 
having the appearance of spore-bearing 
cells, simulated by the production of fat 
bodies. In sugar-containing media egg- 
shaped cells, measuring as a rule 2.0 to 2.5 
by 2.5 to 3.5 microns, are frequently found. 
Gram-negative. 

Color: Anaerobic cultures develop with 
brown color, ranging in shade from a light, 
dirty greenish brown to a dark brown. Cul- 
tures grown in the presence of oxygen are 
distinctly red. As in the case of Rhodopseudo- 
monas capsulata, the brown color of an 
anaerobic culture can be changed to red by 
shaking with air, light stimulating the color 
change. Color due to bacteriochlorophyll 
and carotenoid pigments. The large major- 
ity of cultures of this species produce, in 
addition, a water-soluble, non-carotenoid, 
bluish red pigment which diffuses into the 
culture medium. 



58 



ORDER I. PSEUDOMONADALES 



Gelatin is not liquefied, and growth with 
single amino acids appears somewhat er- 
ratic. No definite correlations have been 
observed. 

Development is possible over a wide pH 
range, extending from at least 6.0 to 8.5. 

All cultures exhibit an unpleasant putrid 
odor. 

Requires for optimal development higher 
concentrations of yeast extract as a supply 
of growth factors than either Rhodopseudo- 
7nonas palustris or Rhodopseudomonas capsu- 
lata and is more sensitive to low fatty acid 
concentrations. With 0.2 per cent propionate 
in a neutral medium, no growth occurs; 
caproic and pelargonic acids are toxic in 
concentrations below 0.1 per cent. On the 
other hand, tartrate and gluconate can serve 
as oxidation substrates, as can also ethanol, 
glycerol, mannitol, sorbitol, glucose, fruc- 
tose and mannose in 0.2 per cent concentra- 
tions. 

In sugar-containing media, acid is pro- 
duced; the pH ma}^ drop to below 4.0 before 
development ceases. Acid production from 
glucose occurs both in presence and absence 



of air, and in illuminated as well as in non- 
illuminated cultures. In cultures exposed to 
light, the acid usually disappears later on. 

Thiosulfate is not oxidized; hydrogen 
oxidation has not been observed. 

Oxygen does not prevent growth; colonies 
develop on the surface of agar plates ex- 
posed to air, with a red pigmentation. 
Capable of strictly anaerobic development 
in illuminated cultures by photosynthesis. 

Thiamin, biotin and nicotinic acid are 
required for growth (Hutner). 

Optimum temperature, below 30° C. 

Distinctive characters: Spherical cell- 
shape in most media; brown color of anaero- 
bic and red pigmentation of aerobic cul- 
tures; growth with 0.2 per cent tartrate, 
gluconate, ethanol, glycerol, mannitol, 
sorbitol, glucose, fructose and mannose; 
failure to grow with 0.2 per cent propio- 
nate. 

Habitat: Regularly found in stagnant 
bodies of water and in mud. 

Illustrations : INIolisch, op. cit., 1907, Plate 
II, fig. 15; van Niel, op. cit., 1944, fig. 7-8, p. 
19; fig. 39-45, p. 96; fig. 46-54, p. 97. 



Genvs II. Rhodospirillum Molisch, 1907, emend, van Niel, 1944- 

(Molisch, Die Purpurbakterien, Jena, 1907, 24; van Niel, Bact. Rev., 8, 1944, 86; the genus 
now includes the genus Phaeospirilhtm Kluyver and van Niel, Zent. f. Bakt., II Abt., 94, 
1936, 396.) 

Rho.do.spi.ril'lum. Gr. noun rhodum the rose; Gr. noun spira a coil, a spiral; M.L. 
dim.neut.n. Spirillum a bacterial genus; M.L. neut.n. Rhodospirillum the rose Spirillum. 

Spiral-shaped bacteria, motile by means of polar flagella. Gram-negative. Contain bac- 
teriochlorophyll and are potentially photosynthetic in the presence of extraneous oxi- 
dizable substances. Molecular oxygen is not produced. Unable to grow in strictly mineral 
media, even when possessed of the ability to utilize hydrogen as oxidizable substrate, due 
to the need for organic nutrilites. Produce accessory pigments causing the cultures, espe- 
cially when grown in the light, to appear in various shades of red to brown. 

The type species is Rhodospirillum rubrum (Esmarch) Molisch. 

Key to the species of genus Rhodospirillum. 

I. Cultures deep red without brownish tinge; characteristic absorption band around 550 
millimicrons. 

1. Rhodospirillum ruhrum. 

II. Cultures reddish brown to orange; characteristic absorption maximum around 520, not 
550, millimicrons. 

A. Cells 0.5 or less micron in width. 

2. Rhodospirillum Julvum. 

B. Cells more than 0.5 micron wide. 

1. Size of cells 0.7 to 0.9 by 5 to 10 microns. 

3. Rhodospirillum molischianum. 

2. Size 1.2 to 1.5 by 14 to 30 microns. 

4. Rhodospirillum photometricum. 



FAMILY II. ATHIORHODACEAE 



59 



1. Rhotlospirillum rubruni (von Es- 
march, 1887) Molisch, 1907. {Spirillum rub- 
rum von Esmarch, Cent. f. Bakt., 1, 1887, 
225; Rhodospirillum giganteum Molisch, Die 
Purpurbakterien, Jena, 1907, 24; Molisch, 
ibid., 25.) 

rub'rum. L. adj. ruber red. 

Cells characteristically spiral-shaped, but 
size of elements variable within wide 
limits, depending upon environmental con- 
ditions during growth. Width of cells from 
0.5 to 1.5 microns; length from 2 to 50 mi- 
crons, and over ; even in a single culture such 
differences may be found. Also the shape and 
size of the spiral coil varies much; it usually 
ranges between 1 to 4 microns in width, and 
from 1.5 to 7 microns in length. In alanine 
media the majority of the cells occur in the 
form of half -circles to complete rings; 
malate media tend to produce much flat- 
tened spirals. In old cultures involution 
forms appear, straightened spirals and ir- 
regularly swollen cells, the latter common in 
media with higher fatty acids. Such cells 
stain irregularly, contain fatty inclusions, 
and are occasionally branched. Young cul- 
tures show active motility, due to polar 
fiagella. Gram-negative. 

Mucus is not produced. In calcium-defi- 
cient media the growth is flocculent, as if 
agglutinated. With an adequate calcium 
supply the growth in liquid media is ho- 
mogeneous, suspended and consists of single 
cells. 

Gelatin is not liquefied; the amino acids 
alanine, asparagine, aspartic and glutamic 
acids are satisfactory oxidizable compounds. 

Color: Ordinarily deep and dark red, 
without any brownish tinge. In ethanol 
media lighter, and a characteristic pink. 
Pigment production markedly influenced by 
oxygen and light. Slants incubated in dark- 
ness present a pale grayish surface growth 
with a faint reddish hue, while often show- 
ing deep-red cell masses in the region 
between glass wall and agar surface where 
development proceeds at low oxygen ten- 
sion. The color is due to bacteriochlorophyll 
and carotenoid pigments. Among the latter, 
spirilloxanthin is quantitatively predomi- 
nant and is responsible for the characteristic 
absorption band at 550 millimicrons. Water- 
soluble, diffusible pigments are not pro- 
duced. 



Development possible over a pH range of 
at least 6 to 8.5, although, as in other cases, 
the combination of an acid reaction and the 
presence of fatty acids may prevent growth. 

Cultures produce a distinctive odor, 
reminiscent of slightly putrid yeast. 

In general, grow well with fatty acids as 
the chief oxidizable substrate; however, are 
prevented from growing by 0.2 per cent 
propionate in a neutral medium. Most sub- 
stituted acids are equally satisfactory, with 
the exception of tartrate, gluconate and 
citrate. In a concentration of 0.2 per cent, 
ethanol is a suitable substrate, whereas 
the carbohydrates and their corresponding 
polyalcohols are not utilized. 

Thiosulfate is not oxidized; molecular hy- 
drogen can be used by some strains. 

Rather microaerophilic; many strains, 
upon initial isolation, incapable of growth 
at atmospheric oxygen tension. Subse- 
quent adaptation can be induced, but even 
such adapted cultures exhibit negative 
chemota.xis to air. 

Capable of strictly anaerobic develop- 
ment in illuminated cultures on the basis 
of a photosynthetic metabolism. 

Biotin is required for growth (Hutner). 

Optimum temperature generally between 
30° and 37° C. 

Distinctive characters: The most im- 
portant characteristics of the species are 
the spiral shape, combined with the ability 
to produce a red pigment with a definite 
absorption maximum at 550 millimicrons 
in the intact cells. Diagnostically useful are 
the good growth in media with 0.2 per cent 
ethanol, alanine, asparagine, aspartate or 
glutamate and the inadequacy of similar 
concentrations of carbohydrates and thio- 
sulfate as substrates. 

Habitat: Regularly present in stagnant 
bodies of water and in mud. 

Illustrations: Molisch, ibid., Plate I, fig. 
5-7; van Niel, Bact. Rev., 8, 1944, fig. 9-10, 
p. 19; fig. 11-16, p. 24; fig. 67-75, p. 103; fig. 
76-84, p. 104; fig. 85-90, p. 106; fig. 91-96, p. 
107. 

2. Rhodospirillum fulvum van Niel, 
1944. (Bact. Rev., 8, 1944, 108.) 

ful'vum. L. adj. fulvus deep or reddish 
j^ellow, tawn3^ 

Characteristic for the species is the very 



60 



ORDER I. PSEUDOMONADALES 



small size of the individual cells. These are 
not over 0.5 micron wide and generally not 
longer than 2.5 microns. The most common 
shape consists of a complete turn of about 
1 by 1.5 microns. In media with fatty acids 
as a substrate the spirals appear somewhat 
steeper than in fumarate, succinate or 
malate cultures. Swollen individuals re- 
sembling vibrios are encountered in cultures 
which do not appear quite healthy. Forma- 
tion of mucus or clumping has not been ob- 
served. 

Gelatin is not liquefied; aspartate has been 
the only amino acid capable of inducing 
growth. Thiosulfate is not oxidized. 

Color: Quite distinct from that of Rhodo- 
spirillum rubrimi; colonies and stab cul- 
tures are a reddish brown while liquid cul- 
tures often appear brownish orange. The 
color is due to bacteriochlorophyll and 
carotenoid pigments; among the latter 
spirilloxanthin, as evidenced by the absence 
of an absorption maximum at 550 milli- 
microns, is not represented as a major con- 
stituent. Does not produce water-soluble, 
diffusible pigments. 

Capable of strictly anaerobic develop- 
ment in illuminated cultures, due to photo- 
synthetic metabolism. 

Fatty acids and the four-carbon dicar- 
boxylic acids are imiformly good substrates; 
glutarate is not used. Ethanol and glucose, 
in a concentration of 0.2 per cent, have 
yielded satisfactory cultures; other carbo- 
hydrates, as well as the corresponding poly- 
alcohols, have given negative results. 

Little information available concerning 
pH and temperature relations. Behaves 
generally as a strict anaerobe; adaptation 
to microaerophilic conditions has not been 
achieved. Negative aerotaxis very pro- 
nounced. 

Distinctive characters : The small size and 
the color of the cultures serve as adequate 
criteria for its differentiation from Rhodo- 
spirilhim ruhrum. The strictly anaerobic 
nature and the failure to grow with glu- 
tarate and various amino acids except as- 
partate can probably be used as supple- 
mentary specific properties. 

Habitat: Bodies of stagnant water and 
mud . 

Illustrations: Van Niel, ibid., fig. 97-102, 



p. 109; Giesberger, Jour. Microb. and Serol., 
13, 1947, fig. 1-2, p. 141. 

3. Rhodospirilluin niolischianuni 

Giesberger, 1947. (Jour. Microbiol, and 
Serol., 13, 1947, 137.) 

mo.li.schi.an'um. M.L. adj. molischianus 
pertaining to Molisch. 

Cells characteristically spiral -shaped, 
moderately large, 0.7 to 0.9 by 5 to 10 mi- 
crons. Mostly with one or two complete 
turns which vary in width from 1.3 to 2 
microns and in length from 4 to 6 microns; 
this depends upon environmental condi- 
tions. 

Color: Distinctly reddish brown due to 
the presence of bacteriochlorophyll and 
carotenoids, the latter responsible for the 
absorption maxima at 520 and 485 milli- 
microns. Spirilloxanthin absent. 

Capable of development under stricth^ 
anaerobic conditions in media containing 
ethanol or fatty- or hydroxy-acids as oxidiz- 
able substrates. Citrate can also be utilized 
in this manner, but not glycerol, glucose, 
hydrogen sulfide or thiosulfates. Tends to be 
strictl}^ anaerobic, and hence capable of 
development onlj- in illuminated cultures. 

Does not liquefy gelatin. 

Distinctive characters : The absence of an 
absorption band at 550 millimicrons and the 
ability to utilize citrate serve to distinguish 
this type from Rhodospirillum ruhrum, 
which it closely resembles in size and shape. 
The individual cell size differentiates this 
species from R. fulvum and R. photometri- 
cum. 

Habitat: Widely distributed. Regularly 
present in stagnant water and mud; can be 
found in abundance in anaerobic cultures of 
hay extract inoculated with such materials 
and incubated in light. 

Illustrations: Giesberger, ibid., fig. 3-5, 
p. 141. 

4. Rhodospirillum photonietricum 

Molisch, 1907. (Die Purpurbakterien, Jena, 
1907, 24.) 

pho.to.me'tri.cum. Gr. noun phos light; 
Gr. adj. metricus measured; M.L. adj. 
photometriciis light-measured. 

Cells large, stout, spiral -shaped. Mostly 
with one or two complete turns whose wave 



FAMILY III. CHLOROBACTERIACEAE 61 

length varies in width from 4 to 6 microns glucose, hydrogen sulfide or thiosulfates. 

and in length from 7 to 10 microns; this is Strongly microaerophilic; tends to be 

dependent upon environmental conditions. strictly anaerobic, and hence capable of 

Actively motile by means of a single polar development only in illuminated cultures, 

flagellum. Does not liquefy gelatin. 

Color: Distinctly reddish brown due to Distinctive characters: Readily distin- 

the presence of bacteriochlorophyll and guishable from Rhodospirillum rubrum by 

carotenoids, the latter responsible for the the absence of an absorption band at 550 

absorption maxima at 520 and 485 milli- millimicrons and from R. fulvum and R. 

microns. Spirilloxanthin not formed. molischianum by the greater size of its cells. 

Capable of development under strictly Habitat: Stagnant water and mud; widely 

anaerobic conditions in media containing distributed. 

ethanol, fatty acids or hydroxy acids as Illustrations: Molisch, ibid., Plate 1, fig. 

oxidizable substrates. Citrate can also be 5-6; Giesberger, Jour. Microbiol, and Serol., 

utilized in this manner, but not glycerol, 13, 1947, fig. 6-9, p. 141. 



FAMILY III. CHLOROBACTERIACEAE LAUTERBORN, 1913. 

{Chlorobakteriaceae (sic) Lauterborn, Alg. Bot. Ztschr., 19, 1913, 99.) 

Chlo.ro. bac.te.ri.a'ce.ae. M.L. neut.n. Chlorobacterium type genus of the family; -aceae 
ending to denote a family; M.L. fern. pi. n. Chlorobacteriaceae the Chlorobacterium family. 

Green bacteria, usually of small size, occurring singly or in cell masses of various shapes 
and sizes, developing in environments containing rather high concentrations of hydrogen 
sulfide and exposed to light. As a rule not containing sulfur globules but frequently de- 
positing elemental sulfur outside the cells. Contain green pigments of a chlorophyllous 
nature, though not identical with the common green plant chlorophylls nor with bacterio- 
chlorophjdl. Capable of photosynthesis in the presence of hydrogen sulfide; do not liberate 
oxygen. 

A number of genera have been proposed; some are characterized by special colonial growth 
forms while others are characterized on the basis of a supposed symbiotic habitus where 
the green bacteria grow in more or less characteristic aggregates together with other micro- 
organisms. In view of the variations in size and shape exhibited by the only member of this 
group which has so far been obtained and studied in pure culture (van Niel, Arch, f . Mikro- 
hio\.,3, 1931, 65ff.), the validity of many of these genera is doubtful. The following keys and 
descriptions, therefore, bear a strictly provisional character. Here, as in the case of the 
sulfur purple bacteria, significant advances can only be expected from pure-culture studies 
under controlled environmental conditions. 

Key to the genera of family Chlorobacteriaceae. 

I. Free-living bacteria not intimately associated with other microbes. 

A. Bacteria not united into well defined colonies. 

Genus I. Chlorobium, p. 62. 

B. Bacteria united into characteristic aggregates. 

1. Bacteria without intracellular sulfur globules. 

Genus II. Pelodictyon, p. 63. 

2. Bacteria with intracellular sulfur globules. 

Genus III. Clathrochloris, p. 64. 
II. Green bacteria found as symbiotic aggregates with other organisms. 
A. Aggregates composed of green bacteria and protozoa. 

Genus IV. Chlorobacterium, p. 65. 



62 ORDER I. PSEUDOMONADALES 

B. Aggregates composed of two different types of bacteria. 

1. Aggregates small, barrel -shaped, actively motile and consisting of a central, polar 
flagellate, rod-shaped bacterium with a covering of sulfur green bacteria. 

Genus V. Chlorochromatium, p. 65. 

2. Aggregates large, cylindrical, non-motile and composed of a central filamentous 
bacterium with a more or less extensive covering of sulfur green bacteria. 

Genus VI. Cylindrogloea, p. 66. 

Genus I. Chlorobium Nadson, 1912. 

(Bull. Jard. Imper. Botan., St. P^tersb., 12, 1912, 64 (Russian), 83 (German).) 
Chlo.ro 'bi.um. Gr. adj. chlorus greenish yellow, green; Gr. noun hios life; M.L. neut.n. 
Chlorobium green life. 

Sulfur green bacteria, occurring singly or in chains, individual cells of various sizes and 
shapes, from spherical to relatively long rod -shaped, the latter sometimes coiled into tight 
spirals; often united in chains and generally embedded in a slime capsule. Non-motile. 
Gram-negative. Contain a chlorophjdlous pigment different from the common green plant 
chlorophylls and from bacteriochlorophyll. Capable of photosynthesis in the presence of 
hydrogen sulfide, during which thej^ produce elemental sulfur which is excreted outside the 
cells. Do not form spores. 
The tj^pe species is Chlorobium limicola Nadson. 

Key to the species of genus Chlorobium. 

I. Does not utilize thiosulfates as oxidizable substrate. 

1. Chlorobium limicola. 
II. Utilizes thiosulfates as oxidizable substrate. 

2. Chlorobium thiosulfatophihan. 

1. Chlorobium limicola Nadson, 1912. appearance of the cultures. In healthy cul- 

(Bull. Jard. Imper. Botan., St. Petersb., 12, tures the bacteria rem.ain evenly dispersed 

1912, 64 (Russian), 83 (German).) and settle very slowly. Non-motile. 

li.mi'co.la. L. noun limus mud; L. v. colo Color: Intensely green in healthy cul- 
to dwell; M.L. fem.n. limicola the mud tures; poor pigmentation and then yellow- 
dweller, ish green in media deficient in iron. 

Cells occur in various sizes and shapes Strictly anaerobic, obligatory photosyn- 
which are markedly dependent upon en- thetic bacteria whose occurrence in nature 
vironmental conditions. In young and is dependent upon the presence of hydrogen 
healthy cultures, predominantly small, sulfide. They utilize this substance, as well 
ovoid to short rods, 0.7 by 0.9 to 1.5 microns, as elemental sulfur and molecular hydrogen, 
frequently united in chains resemblingstrep- as oxidizable substrates; produce sulfur 
tococci. Greatly elongated and irregularly from sulfides but do not store sulfur glob- 
bent and curved rods also occur as involu- ules inside the cells. Oxidation of sulfide 
tion forms; these rods may likewise remain may yield sulfur as an end product, but 
united in chains. Club-shaped and spirally under optimal conditions the sulfur is 
wound to tightly coiled involution forms further oxidized to sulfate. Unable to use 
have been described, but the conditions for thiosulfate and tetrathionate as oxidizable 
their formation are not understood, and in substrates. Development in organic media 
recent pure-culture studies these have never free of sulfide has not been obtained, 
been encountered (Larsen, Jour. Bact., 64, Source: Isolated from mud and stagnant 
1952, 187). Regularly produce mucus; in water, containing hydrogen sulfide, from 
media of inadequate composition this may the St. Petersburg Botanical Garden. Also 
lead to the formation of cell conglomerates found by Bicknell (Lloydia, 12, 1949, 183) in 
of different sizes and shapes and a stringy Sodon Lake, Bloomfield Hills, Michigan. 



FAMILY III. CHLOROBACTERIACEAE 



63 



Habitat: Widely distributed in mud and 
stagnant water. Mass development under 
conditions of relatively high sulfide con- 
centrations and low pH in environments 
exposed to light. 

Illustrations: Nadson, up. cit., 1912, PI. 
Ill, fig. 3-12; van Niel, Arch. f. Mikrobiol., 
3, 1931, fig. 8, p. 66. 

2. Chlorobiuin ihiosulfatophilum Lar- 

sen, 1952. (Jour. Bact., 64, 1952, 187.) 

thi.o.sul.fa.to'phi.lum. M.L. noun thio- 
sulfatum thiosulfate; Gr.adj. phibis loving; 
M.L. adj. thiosulfatophilus thiosulfate- 
loving. 



Cells indistinguishable from those of 
Chlorobium limicola. 

Color: As in Chlorobium limicola. 

Strictly anaerobic, obligatory photosyn- 
thetic bacteria. Utilize sulfides, sulfur, 
thiosulfate, tetrathionate and molecular 
hydrogen as o.xidizable substrates; produce 
sulfate from inorganic sulfur compounds. 
Unable to grow in organic media free of oxi- 
dizable, inorganic sulfur compounds. 

Distinctive characters: Differs from 
Chlorobium limicola in its ability to oxidize 
thiosulfate and tetrathionate. 

Source: Isolated from marine and fresh- 
water mud. 

Habitat: Same as for Chlorobium limicola. 



Genus II. Pelodictyon Lauterborn, 1913. 

(Allgem. botan. Ztschr., 19, 1913, 98; Verhandl. naturhistor.-medizin. Vereins, Heidel- 
berg, N.F. 13, 1915, 431.) 

Pe.lo.dic'ty.on. Gr. adj. pelos dark-colored; Gr. noun dictyon net; M.L. neut.n. Pelodic- 
tyon a dark-colored net. 

Sulfur green bacteria, individual cells ovoid to distinctly rod-shaped, producing rather 
extensive mucoid capsules and generally united into large colonies of characteristic shapes. 
Non-motile. Contain chlorophyllous pigments different from the common green plant 
chlorophylls and from bacteriochlorophyll. Capable of photosynthesis in the presence of 
hydrogen sulfide, but do not store sulfur globules inside the cells. 

The type species is Pelodictyon clathratiforme (Szafer) Lauterborn. 

Key to the species of genus Pelodictyon. 

I. Cells united in colonies in a net-like fashion. 

1. Pelodictyon clathratiforme. 
II. Cells arranged in tightly packed colonies without net-like structure. 

A. Colonies composed of irregularly arranged cell-masses, extending in three dimen- 
sions. 

2. Pelodictyon aggregatum. 

B. Colonies consisting of parallel strands and extending in two dimen.sions. 

3. Pelodictyon parallelum. 



1. Pelodictyon clathratiforme (Szafer, 
1910) Lauterborn, 1913. (Aphanothece clath- 
ratiforme Szafer, Bull. Acad. Sci., Cracovie, 
Ser. B, 3, 1910, 162; Lauterborn, Allgem. 
botan. Ztschr., 19, 1913, 98; also see Ver- 
handl. naturhist.-medizin. Vereins, Heidel- 
berg, N.F. 13, 1915,430.) 

clath.ra.ti.for'me. L. part. adj. clathratus 
latticed; L. noun forma shape, form; M.L. 
adj. clathratiformis lattice-like. 

Cells generally rod-shaped, ranging from 
slightly elongated ovoids to distinct rods, 



often vacuolated, about 0.5 to 1.5 by 2 to 4 
microns, producing rather wide slime cap- 
sules. Characteristically united into three- 
dimensional colonies which present a 
net-like appearance with mazes of about 10 
to 50 microns. Non-motile. 

Color: Yellowish green. 

Abnormal cell forms (involution forms) 
not uncommon, consisting of elongated and 
curved, forked, or club-shaped and swollen 
rods, occasionally suggesting rudimentary 
branching at the extremities. Such cells 



64 



ORDER I. PSEUDOMONADALES 



may be found as elements in chains for the 
greater part composed of normal individ- 
uals. 

Habitat: Mud and stagnant water con- 
taining rather high concentrations of hy- 
drogen sulfide and exposed to light; sulfur 
springs. 

Illustrations: Szafer, op. cit., 1910, PI. 
VI, fig. 5; Perfiliev, Jour. Microbiol. (Rus- 
sian), 1, 1914, PI. II, fig. 1, 5-12; Lauter- 
born, op. cit., 1915, PI. Ill, fig. 33. 

2. Pelodictyon aggregatuin Perfiliev, 
1914. (Aphanothece luteola Schmidle, Bei- 
hefte Botan. Cent., 10, 1901, 179; Perfiliev, 
Jour. Microbiol. (Russian), 1, 1914, 197.) 

ag.gre.ga'tum. L. part. adj. aggregatus 
added to a flock, aggregated, clumped. 

Cells usually rod-shaped, about 1 to 1.5 
by 2 to 4 microns, often vacuolated, produc- 
ing slime capsules and united into irregu- 
larly shaped, three-dimensional colonies in 
which the cells are more or less tightly 
packed without orderly arrangement. Colo- 
nies may attain a size of up to 1 mm; fre- 
quently they are not fully compact but 
contain less dense areas or appear perfo- 
rated, thus forming transition stages to 
Pelodictyon claihratiforme. Non-motile. 

Color: Yellowish green. 

Abnormal cell forms (involution forms) 
usually in the shape of elongated and 
curved, forked or club-shaped and swollen 
rods, occasionally suggesting branching at 
extremities. 

Source: Isolated from sulfureted water in 
Europe ; also reported by Button and Juday 



(Ecology, 25, 1944, 277) from Scaffold Lake, 
Wisconsin. 

Habitat: Mud and stagnant water con- 
taining rather high concentrations of hydro- 
gen sulfide and exposed to light; sulfur 
springs. 

Illustrations: Perfiliev, ibid., PI. II, fig. 
2; Lauterborn, Verhandl. naturhistor.- 
medizin. Vereins, Heidelberg, N.F. 13, 1915, 
PI. Ill, fig. 29-31. 

3. Pelodictyon parallelum (Szafer, 
1910) Perfiliev, 1914. (Aphanothece parallela 
Szafer, Bull. Acad. Sci., Cracovie, Ser. B, 3, 
1910, 163; Perfiliev, Jour. Microbiol. (Rus- 
sian), 1, 1914, 198.) 

pa.ral.le'lum. Gr. adj. parallelus parallel. 

Cells rather small, spherical to ovoid, or 
even rod-shaped; about 0.5 to 1 by 1 to 3 
microns, occurring in chains and forming 
flat, plate-like, two-dimensional aggre- 
gates in which the chains are arranged as 
parallel strands. Non-motile. 

Color: Yellowish green. 

Abnormal cell forms not specifically men- 
tioned, but likely to occur and to resemble 
those of other species. 

This species may well be a special growth- 
form of Chlorobium limicola. 

Habitat: Mud and stagnant water con- 
taining rather high concentrations of hydro- 
gen sulfide and exposed to light; sulfur 
springs. 

Illustrations: Szafer, op. cit., 1910, PI. 
VI, fig. 7; Perfiliev, op. cit., 1914, PI. II, fig. 
2. 



Genus HI. Clathrochloris Geitler, 1925. 

(Geitler, in Pascher, Die Siisswasserflora Deutschlands, Osterreichs und der Schweiz, 
Jena, 12, 1925, 457.) 

Clath.ro. chlo'ris. L. pi. noun clathri lattice; Gr. adj. chlorus green; M.L. fem.n. Clathro- 
chloris green lattice. 

Sulfur green bacteria of small size, generally spherical and arranged in chains which are 
united into loose, trellis-shaped aggregates, somewhat similar to those of Pelodictyon cla- 
thratiforme and Pelodictyon aggregatum. Cells usually contain sulfur globules. Color is yel- 
loivish green. Non-motile. 

The type species is Clathrochloris sulphurica (Szafer) Geitler. 



1. Clathrochloris sulphurica (Szafer, 
1910) Geitler, 1925. {Aphanothece sulphurica 
Szafer, Bull. Acad. Sci., Cracovie, Ser. B, 3, 



1910, 162; Geitler, Die Siisswasserflora 
Deutschlands, Osterreichs und der Schweiz, 
Jena, 12, 1925, 457.) 



FAMILY III. CHLOROBACTERIACEAE 



65 



sul.phur'i.ca. L. noun sulfw' (sometimes 
sulphur) sulfur; IM.L. adj. sulphuricus sul- 
furic. 

Cells spherical, about 0.5 to 0.7 micron 
in diameter, usually containing sulfur glob- 
ules. Non-motile. 

Color: Yellowish green. 

The reported occurrence of sulfur globules 
in the cells of this very small species is sur- 
prising; it is the only one among the sulfur 
green bacteria in which these inclusions 



have been encountered. The published de- 
scriptions are even more fragmentary than 
those of other members of the group. 

Source : Reported only from sulfur springs 
in Lubien Wielki, near Lwow, Poland. 

Habitat: Mud and stagnant water con- 
taining rather high concentrations of hj^- 
drogen sulfide and exposed to light; sulfur 
springs. 

Illustration: Szafer, op. cit., 1910, PI. VI, 
fig. 6. 



Genus IV. Chlorohaclerium Lauterborn, 1915. 

(Luuterborn, Verhandl, naturhist.-medizin. Vereins, Heidelberg, N.F., 13, 1915, 429; not 
Chlorobacteriwn* Guillebeau, Landw. Jahrb. d. Schweiz, 4, 1890, 32.) 

Chlo.ro. bac.te'ri.um. Gr. adj. chlonis green; L. noun bacterium a small rod; M.L. neut.n. 
Chlorobacterium a green rodlet. 

Sulfur green bacteria(?) which grow sj'mbiotically as an outside covering on cells of pro- 
tozoa, such as amoeba and flagellates. Cells rod-shaped, often slightly curved, greenish. 
Non-motile. 

The type species is Chlorobacterium symhioticum Lauterborn. 



1. Chlorobacterium symbioticum Lau- 
terborn, 1915. (Verhandl. naturhist.-medi- 
zin. Vereins, Heidelberg, X.F., IS, 1915, 
429.) 

sym.bi.o'ti.cum. Gr. adj. stjnibioticus of 
companionship, sj'mbiotic. 

Cells rod-shaped, about 0.5 by 2 to 5 
microns, often slightly curved. Non-motile. 

Occur as a peripheral covering of certain 
protozoa with which they may form a sym- 
biotic unit. 

It is not certain that this is a sulfur green 



bacterium: the descriptions of localities 
Avhere it was found fail to mention the pres- 
ence of hydrogen sulfide in the environ- 
ment; this should be a prerequisite for a 
member of this group. 

Source : Reported from a number of pools 
in Germany. 

Habitat: Stagnant water. 

Illustrations: Lauterborn, loc. cit., PL III, 
fig. 34-36; Pascher, Die Siisswasserflora 
Deutschlands, Osterreichs und der Schweiz, 
Jena, 12, 1925, fig. 149. 



Genus V . Chlorochromatiuni Lauterborn, 1906. 
(Allgem. botan. Ztschr., 19, 1906, 196.) 

Chlo.ro. chro.ma'ti.um. Gr. adj. chlorus green; Gr. noun chromatium color, paint; M.L. 
neut.n. Chromatium a bacterial genus; M.L. neut.n. Chlorochromatium a green Chromatium. 

Sulfur green bacteria, ovoid to rod -shaped with rounded ends. Occur as barrel -shaped 
aggregates consisting of a rather large, colorless, polar flagellate bacterium as the center 
which is surrounded by green bacteria, arranged in 4 to 6 rows, ordinaril}' from 2 to 4 cells 
high. The entire conglomerate behaves like a unit, is motile, and multiplies by the more or 
less simultaneous fission of its components. 

The green constituents contain a chlorophyllous pigment which is not identical with the 
common green plant chlorophylls or with bacteriochlorophjdl. Capable of photosj-nthesis 
in the presence of hydrogen sulfide but do not store sulfur globules in the cells. 

The type species is Chlorochromatium aggregatum Lauterborn. 



* It has been proposed that Chlorobacterium Guillebeau be rejected as a generic name in 
bacteriology and placed in the list of nomina generica rejicienda (Internat. Bull. Bact. 
Nomen. and Tax., 1, 1951, 43 and 2, 1952, 110). 



GG 



ORDER I. PSEUDOMONADALES 



1. Chlorochromatium aggregatum 

Lauterborn, 1906. (AUgem. botan. Ztschr., 
19, 1906, 196.) 

ag.gre.ga'tum. L. part. adj. aggregatus 
flocked together, clumped. 

Cells of the green component 0.5 to 1.0 by 
1.0 to 2.5 microns, mostly from 8 to 16 in- 
dividuals surrounding the central bac- 
terium. Size of the total barrel-shaped unit 
variable, generally 2.5 to 5 by 7 to 12 mi- 
crons. Occasionally a group of the complex 
colonies may remain attached in a chain. 

Anaerobic. 

Habitat: Mud and stagnant water con- 
taining rather high concentrations of hydro- 
gen sulfide and exposed to light. 



There is at present no good reason for 
distinguishing 2 varieties (forma typica and 
forma minor) or even species, on the basis 
of size differences of the colony, as Geitler 
proposed (Die Siisswasserflora Deutsch- 
lands, Osterreichs und der Schweiz, Jena, 
12, 1925, 460). The reported and personally 
observed sizes of such units show that the 
extreme limits are linked by a complete 
series of transitions. 

Illustrations: Buder, Ber. deut. botan. 
Ges., 31, 1914, Generalversam., PI. XXIV, 
fig. 1-5; Perfiliev, Jour. Microbiol. (Rus- 
sian), 1, 1914, fig. 1-5, p. 213. 



Genus VI. Cylindrogloea Perfiliev, 1914- 
(Jour. Microbiol. (Russian), 1, 1914, 223.) 

Cy.lin.dro.gloe'a. Gr. noun cylindrus cylinder; Gr. novm gloea gum; M.L. fem.n. Cylin- 
drogloea cylindrical gum. 

Sulfur green bacteria consisting of small ovoid to rod-shaped cells growing in association 
with a filamentous, colorless, central bacterium, thus forming colonies of a cylindrical 
shape. Non-motile. The green component contains a chlorophyllous pigment different from 
the common chlorophylls of green plants and from bacteriochlorophyll. Capable of photo- 
synthesis in the presence of hydrogen sulfide without depositing sulfur globules in the cells. 

The type species is Cylindrogloea bacterifera Perfiliev. 



1. Cylindrogloea bacterifera Perfiliev, 
1914. (Jour. Microbiol. (Russian), 1, 1914, 
223.) 

bac.te.ri'fe.ra. Gr. neut.n. bactrum a rod; 
M.L. mas.n. bacter rod (a combining form); 
L. verbal suf. fer bearing; M.L. adj. bac- 
terifera rod-bearing. 

Individual green components ovoid to 
rod-shaped, about 0.5 to 1 by 2 to 4 microns, 
very similar to those of the complex Chloro- 
bacterium symbioiicum and Chlorochromatium 
aggregatum with which they may well be 
identical. The central filamentous bac- 
terium is embedded in a slime capsule of 
considerable dimensions. This, in turn, is 
surrounded by a layer of green bacteria, 
usually one cell thick. The green organisms 
may form a very dense outer covering, or 
they may be more sparsely distributed over 
the slime capsule. The entire unit is again 
surrounded by a sizeable slime zone. Aggre- 
gates measure about 7 to 8 microns in width 
and up to 50 microns in length; they are non- 



motile. Both components appear to be 
non -spore-forming. 

Habitat: Mud and stagnant water con- 
taining rather high concentrations of hj^dro- 
gen sulfide and exposed to light. 

Illustration: Perfiliev, ibid., fig. 6-11, p. 
213. 

Perfiliev rightly emphasizes, as Buder had 
done for Chloronium mirabile, the provi- 
sional nature of thus using a generic desig- 
nation for an apparently stable complex 
composed of two different organisms. It re- 
mains possible that the last three genera of 
symbiotic entities represent fortuitous com- 
binations whose occurrence is conditioned 
by environmental factors. If so, the generic 
terminology would be devoid of any taxo- 
nomic significance, and the green bacteria 
should be relegated to more appropriate 
genera. Indications suggestive of this state 
of affairs can be found in the literature ; for 
example in Utermohl's observation (Archiv 



FAMILY I. NITROBACTERACEAE 67 

f. Hydrobiol., Suppl. 5, 1925, 279) that the grate, whereupon the green constituents 

complex Chlorochromatium aggregalum may, appear as small Pelodictyon aggregatum 

especially in the presence of oxygen, disinte- {Schmidlea luteola) colonies. 



Suborder II. Pseiidomonadineae Breed, Murray and Smith, Sub-Ordo Nov. 

Pseu.do.mo.na.di'ne.ae. M.L. fem.n. Pseudomonas, -adds a genus of bacteria; -ineae end- 
ing to denote a suborder; ALL. fern. pi. n. Pseiidovionadineae the Pseudomonas suborder. 

Cells normally about 1 micron in diameter, but among the colorless sulfur bacteria they 
may be as much as 14 microns in diameter. The cells do not contain photosynthetic pig- 
ments, but diffusible, water-soluble pigments of a type not found elsewhere among bacteria 
occur in many species. Also, non-water-soluble yellow or red pigments occur in some gen- 
era. The motile species are invariably polar flagellate. Some groups are strictly autotrophic, 
oxidizing simple inorganic compounds; others are also oxidative but are facultatively 
heterotrophic or heterotrophic in their physiology. A few genera include species that fer- 
ment simple sugars, even producing H2 and CO2 as do the common acid- and gas-producing 
coliform bacteria. The organisms in one genus {Zijmomonas) even carry out an alcoholic 
fermentation similar to that of j^easts. The majority of the species grow well and fairly 
rapidly on the surfaces of ordinary culture media. Some species that attack agar or cellulose 
or that show other unusual types of physiology are more fastidious in their requirements. 
Only a few species are strictly anaerobic as in Vibrio and Desulfovibrio . The species in this 
suborder are largely found in salt- or fresh-water or in soil. Some are parasitic and a few 
are pathogenic to vertebrates including man. 

Key to (he families of siihordcr Pseiidomonadineae. 

I. Coccoid to rod-shaped cells. Occasionally individual rods may be curved although the 
majority of the cells are straight. 

A. Cells not attached to a substrate. 

1. Cells have the power to oxidize simple compounds such as ammonia, nitrites, 
methane, hydrogen, carbon monoxide, sulfur or sulfur compounds. Chemo-auto- 
trophic or facultatively chemo-autotrophic. 

a. Do not secure their energy from the oxidation of sulfur compounds, 
b. Oxidize ammonia to nitrites or nitrites to nitrates. Autotrophic. 
Family I. Nitrobacteraceae, p. 68. 
bb. Oxidize methane, hydrogen or carbon monoxide. Autotrophic. 
Family II. Methanomonadaceae , p. 74. 
aa. Oxidize sulfur compounds, frequently with a deposit of free sulfur granules 
or crystals within or without the cells. 

Family III. Thiobacteriaceae, p. 78. 

2. Cells frequently oxidative, although they are sometimes fermentative in their 
physiology. Usually heterotrophic. Rarely facultatively autotrophic 

Family IV. Pseudomonadaceae, p. 88. 

B. Cells in free-floating films or attached to a substrate. 

a. Cells attached to the substrate by means of a stalk, usually with a holdfast. 
Family V. Caulobacteraceae , p. 212. 
aa. Cells in free-floating films or attached to the substrate by means of capsular 
material. 

Family VI. Siderocapsaceae, p. 217. 
II. Curved, vibrio-like to spiral-shaped cells. 

Family VII. Spirillaceae, p. 228. 



68 ORDER I. PSEUDOMONADALES 

FAMILY I. NITROBACTERACEAE BUCHANAN, 1917.* 
(Jour. Bact., 2, 1917, 349 and Jour. Bact., S, 1918, 179.) 

Ni.tro.bac.te.ra'ce.ae. M.L. A^ z'^rofeacier name of type genus of the family; -aceae ending 
to denote a family; M.L. plural noun Nitrohacteraceae the Nitrobacter family. 

Cells without endospores; rod-shaped, ellipsoidal or even spherical (Nitrosococcus) or 
spirillar in shape (Nitrosospira) . Flagella polar, occasionally absent. Gram-negative. Or- 
ganisms which derive energy from the oxidation of ammonia to nitrite or from the oxida- 
tion of nitrite to nitrate; these bacteria depend on this oxidation for growth and fail to grow 
on media containing organic matter in the absence of the specific inorganic materials used 
as sources of energy. Many organic compounds commonly used in standard culture media 
are toxic to these bacteria. Not parasitic. Commonly found in soil and fresh water. 

The type genus for the family is Nitrobacter Winogradsky. 

As it appears to be a more logical arrangement, the genera that include the species that 
oxidize ammonia are discussed first although the type genus does not belong in this group. 

Key to the genera of family Nitrohacteraceae. 

I. Ammonia oxidized to nitrite. 

A. Zoogloeae not formed. Cells occur separately, free or in dense aggregates. 

1. Cells not spiral -shaped. 

a. Cells ellipsoidal. 

Genus I. Nitrosomonas, p. 68. 
aa. Cells spherical. 

Genus II. Nitrosococcus, p. 69. 

2. Cells spiral. 

Genus III. Nitrosospira, p. 70. 

B. Zoogloeae formed. 

1. Zoogloea surrounded by a common membrane forming a cyst. 

Genus IV. Nitrosocystis, p. 70. 

2. No common membrane surrounds the cells. The massed cells are embedded in 
slime. 

Genus V. Nitrosogloea, p. 71. 
II. Nitrite oxidized to nitrate. 

A. Zoogloeae not formed. 

Genus VI. Nitrobacter, p. 72. 

B. Zoogloeae formed. 

Genus VII. Nitrocystis, p. 73. 

Genus I. Nitrosomonas Winogradsky , 1890. 

{Nitromonas Winogradsky, Ann. Inst. Past., 4, 1890, 257; not Nitromonas Orla-Jensen, 
Cent. f. Bakt., II Abt., 22, 1909, 334; Arch. Sci. biol., St. Petersburg, 1, 1892, 127; emend. 
S. and H. Winogradsky, Ann. Inst. Past., 50, 1933, 393.) 

Ni.tro.so.mo'nas. M.L. nitrosus nitrous; Gr. monas, monadis a unit, monad; M.L. fem.n. 
Nitrosomonas nitrous monad, i.e., the monad producing nitrite. 

Cells ellipsoidal, non-rhotile or with a single polar flagellum, occurring singly, in pairs, 
short chains or irregular masses which are not enclosed in a common membrane. O.xidize 
ammonia to nitrite more rapidly than the other genera of this family. 

The type species is Nitrosomonas europaea Winogradsky. 

* Completely revised by Dr. R. L. Starkey, New Jersey Agricultural Experiment Station, 
New Brunswick, N. J., March, 1943; minor revisions, November, 1953. 



FAMILY I. NITROBACTERACEAE 



1. Nitrosomonas europaea Winograd- 
sky, 1892. (Arch. Sci. biol., St. Petersburg, 
1, 1892, 127.) 

eu.ro. pae'a. Gr. adj. europaeus of Europe, 
European. 

Rods, 0.9 to 1.0 by 1.1 to 1.8 microns, oc- 
curring singly, rarely in chains of three to 
four. Possess a single polar flagellum 3 to 4 
times the length of the rods, or rarely one 
at either end. 

Grow readily in aqueous media without or- 
ganic matter and containing ammonium 
sulfate, potassium phosphate and mag- 
nesium carbonate. The cells accumulate in 
soft masses around the particles of mag- 
nesium carbonate at the bottom of the flask. 
The liquid is occasionally turbid through 
development of motile swarm cells or 
monads. 

Small, compact, sharply defined colonies 
brownish in color on silica gel. 

Aerobic. 

Strictly autotrophic. 

Source: Soils of Zurich, Switzerland; of 
Gennevilliers, France; and Kazan, Russia. 

Habitat: Presumably widely distributed 
in soil. 

2. Nitrosomonas monocella Nelson, 
1931. (Zent. f. Bakt., II Abt., 83, 1931, 287.) 

mon.o.cel'la. Gr. monus single; L. cella 
oom, cell; M.L. adj. monocellus one-celled. 



Ovoid rods, 0.6 to 0.9 micron, often oc- 
curring in pairs. Young cells nearly spheri- 
cal. Motile by means of a single polar 
flagellum 3 to 5 times as long as the rod. 
Gram-positive (Nelson). Found negative by 
H. J. Conn (personal communication). 

No growth in nutrient broth, nutrient 
agar, nutrient or plain gelatin, plain or lit- 
mus milk, glucose or plain yeast water, or on 
potato. 

Silica gel or agar plates of inorganic 
medium: No typical colonies, but yellowish 
brown masses of growth around particles of 
CaCOs in the medium. 

Inorganic liquid medium containing 
ammonium salts: Uniform development 
throughout the liquid as well as in the 
carbonate sediment. 

Even low concentrations of organic mat- 
ter retard or completely inhibit the initia- 
tion of growth. Plant extracts are toxic. 

Free CO 2 and O2 necessary for growth. 

Optimum pH, 8.0 to 9.0. Poor growth 
below pH 7.0. Some growth above pH 9.0. 

Optimum temperature for growth and oxi- 
dation, 28° C. 

Aerobic . 

Strictly autotrophic. 

Source: Isolated from field soil. 

Habitat: Presumably widely distributed 
in soil. 



Genus II. Nitrosococcus Winogradshj, 1892. 
(Arch. Sci. biol., St. Petersburg, 1, 1892, 127.) 
Ni.tro.so.coc'cus. M.L. nitrosus nitrous; Gr. coccus grain, berry; M.L. mas.n. Nitroso- 
coccus nitrous sphere. 

Cells large spheres, non-motile, not producing zoogloeae. Oxidize ammonia to nitrite. 
The type species is Nitrosococcus nitrosus (Migula) Buchanan. 



1. Nitrosococcus nitrosus (Migula, 
1900) Buchanan, 1925. {Nitrosococcus Wino- 
gradsky, Ann. Inst. Past., 5, 1891, 577; 
Arch. Sci. biol., St. Petersburg, 1, 1892, 127; 
Micrococcus nitrosus Migula. Sj^st. d. Bakt., 
2, 1900, 194; Buchanan, Gen. Syst. Bact., 
1925, 402.) 

ni.tro'sus. M.L. adj. nitrosus nitrous. 

Large spheres, 1.5 to 1.7 microns in size, 
with thick cell membranes. Motility could 
not be demonstrated. Stain readily with 



aniline dyes. Zoogloea formation not ob- 
served. Gram-positive (Omelianski, Cent. f. 
Bakt., II Abt., 19, 1907, 263). 

Liquid medium: Turbid. 

Silica gel: Both dark and light colonies. 
Surface colonies look like small drops of a 
turbid yellowish liquid. 

Aerobic. 

Optimum temperature, lietween 20° and 
25° C. 

Source: Isolated from .soil from (^uito. 



70 ORDER I. PSEUDOMONADALES 

Ecuador; Campinas, Brazil; and Melbourne, Habitat: Presumably widely distributed 

Australia. in soil. 

Genus III. Nitrosospira Winogradsky, 1931. 

(S. Winogradsky, Compt. rend. Acad. Sci., Paris, 192, 1931, 1004; S. Winogradsky 
and H. Winogradsky, Ann. Inst. Past., 50, 1933, 394 and 406.) 

Ni.tro.so.spi'ra. M.L. nifrosus nitrous; Gr. spira a coil, spiral; M.L. fem.n. Nitrosospira 
nitrous spiral. 
Cells spiral-shaped. Oxidize ammonia to nitrite very slowly. 
The type species is Nitrosospira briensis S. Winogradsky and H. Winogradsky. 

1. Nitrosospira briensis S. Winogradsky Habitat: Presumably widely distributed 

and H. Winogradsky, 1933. (Ann. Inst. in soil. 
Pasteur, 50, 1933, 407.) 

bri.en'sis. French Brie, place name; M.L. 2. Nitrosospira antarctica S. Wino- 

adj. briensis of Brie. gradsky and H. Winogradsky, 1933. (Ann. 

Spirals wound tightly to form very small Inst. Past., 50, 1933, 407.) 

cylinders as long as 15 to 20 microns. Short ant. arc 'tic. a. Gr. anti opposite; Gr. arcius 

spirals have the appearance of short rods a bear; Gr. adj. antarcticus opposite the 

and ellipsoidal cells. Small pseudo-cocci ob- bear, antarctic, 

served in old cultures. Cells and colonies similar to those of N . 

Colonies on silica gel: Small, occasionally briensis except that the cells are generally 

containing cyst-like aggregates of cells. The wound together to form more compact 

cysts are more poorly developed than in spirals. 

Nitrosocystis. Aerobic. 

Aerobic. Optimum pH, between 7.0 and 7.2. 

Optimum pH, between 7.0 and 7.2. Source: Soil from the Antarctic. 

Source: Uncultivated pasture soil of Brie, Habitat: Presumably widely distributed 

France. in soil. 

Genus IV. Nitrosocystis Winogradsky, 1931. 

(S. Winogradsky, Compt. rend. Acad. Sci., Paris, 192, 1931, 1003; also see S. Winogradsky 
and H. Winogradsky, Ann. Inst. Past., 50, 1933, 394 and 399.) 

Ni.tro.so.cyst'is. M.L. adj. nitrosus nitrous; Gr. noun cystis bladder, cyst; M.L. fem.n. 
Nitrosocystis nitrous cyst. 

Cells ellipsoidal or elongated, uniting in compact, rounded aggregates surrounded by a 
common membrane to form cysts. The cysts disintegrate to free the cells, particularly when 
transferred to fresh media. Within the cyst the cells are embedded in slime. Ammonia is 
oxidized to nitrite at a rate intermediate between that of Nitrosoijionas and that of Nitroso- 
spira. 

Winogradsky and Winogradsky (ibid., 393) differentiated between Nitrosomonas and 
Nitrosocystis in that the former produced soft (or clear) colonies and the latter produced 
hard (or dark) colonies on silica gel. However, Kingma Boltjes (Arch. Mikrobiol., 6, 
1935, 79) was able to obtain both hard and soft colonies in cultures of Nitrosomonas derived 
from single-cell isolates. Meiklejohn (Nature, 168, 1951, 561 ; also see Jour. Soil Sci., 4, 1953, 
62), furthermore, states that the appearance of hard or soft colonies is dependent upon the 
density of the silica gel and upon whether the colonies are in the gel or on the surface; 
consequently she regards Nitrosocystis as probably identical with Nitrosomonas. Some ob- 
servers (Imsenecki, Nature, 157, 1946, 877; and Grace, Nature, 168, 1951, 117; also see 
Riassunti d. Comunicazione, VI Cong. Internaz. d. Microbiol., Roma, 1, 1953, 53) have 



FAMILY I. NITROBACTERACEAE 



71 



suggested that the organisms described in this genus are myxobacters or that the cultures 
were contaminated with myxobacters; however, this does not seem probable. 
The type species is Nitrosocystis javanensis (Winogradsky) Starkey. 



1. Nitrosocystis javanensis (Wino- 
gradsky, 1892) Starkey, 1948. {Nitrosomonas 
javanensis Winogradsky, Arch. Sci. biol., 
St. Petersburg, 1, 1892, 127; Starkey, in 
Manual, 6th ed., 1948, 72.) 

jav.a.nen'sis. Java, a place name; M.L. 
adj. javanensis of Java, Javanese. 

Small ellipsoidal cells having a diameter of 
0.5 to 0.6 micron. Possess a polar flagellum 
20 times as long as the rods. 

In liquid medium produces very compact 
zoogloeal masses of cells and motile swarm- 
ers. The large zoogloeae are themselves 
composed of smaller compact aggregates of 
cells. 

On silica gel the colonies are circular to 
elliptical becoming clear or light brown. 

Aerobic. 

Strictly autotrophic. 

Source: Soil of Buitenzorg, Java; Tokyo, 
Japan; and La Reghaia, Tunisia. 

Habitat: Presumably wddely distributed 
in soil. 

2. Nitrosocystis coccoides Starkey, 
1948. {Nitrosocystis a, S. Winogradsky and 
H. Winogradsky, Ann. Inst. Past., 50, 1933, 



401; Starkey, in Manual, 6th ed., 1948, 72.) 

coc.co.i'des. Gr. coccus grain, berry; Gr. 
idus form, shape; M.L. adj. coccoides coccus- 
shaped. 

Ellipsoidal cells about 1.5 microns in di- 
ameter. Occur as compact aggregates of 
cells imbedded in mucus and surrounded by 
a thickened capsule to form cyst-like bod- 
ies. Cells rarely solitary but more often in 
pairs and in small groups of four or more. 
Probably motile. The mucus which sur- 
rounds the cells is not readily stained 
whereas the outside coating stains more 
easily. 

Colonies on silica gel : As colonies develop, 
the coating of CaCOs on the gel becomes 
yellowish and dissolves, and the colony ap- 
pears as a bulbous, angular, brown body 
which may become 0.5 mm in diameter. 
The cells are held firmly together in these 
irregularly shaped bulbous aggregates. 

Aerobic. 

Source: Poor soils of Brie and elsewhere 
in France. 

Habitat: Presumably widely distributed 
in forest and manured soils. 



Genus V. Nitrosogloea H. Winogradsky, 1935. 
(Compt. rend. Acad. Sci., Paris, £00, 1935, 1887; Ann. Inst. Pasteur, 58, 1937, 335.) 
Ni.tro.so.gloe'a. M.L. nitrosus nitrous; Gr. gloea glue, jelly; M.L. fem.n. Nitrosogloea 
nitrous jelly. 

Cells ellipsoidal or rod-shaped. Embedded in slime to form zoogloeae. No common mem- 
brane surrounds the cell aggregates. Oxidize ammonia to nitrite. 

It has been suggested that these organisms were contaminated with myxobacters. See 
note under Nitrosocystis for references. 
The type species is Nitrosogloea merismoides H. Winogradsky. 



1. Nitrosogloea merismoides H. Wino- 
gradsky, 1935. {Nitrosocystis "I", H. Wino- 
gradsky, Trans. Third Intern. Cong. Soil 
Sci., Oxford, 1, 1935, 139; H. Winogradsky, 
Compt. rend. Acad. Sci., Paris, 300, 1935, 
1887; also see Ann. Inst. Past., 58, 1937, 
333.) 

mer.is.mo.i'des. Gr. merismus a divi- 
sion; Gr. idus form, shape; M.L. adj. meris- 
moides resembling a division. 



Ellipsoidal cells 0.5 by 1.5 microns. Oval 
cells or short rods forming tetards or 
chains, each group with its own sheath. The 
groups vary in shape producing branched 
chains, irregular or compact aggregates. 

Colonies on silica gel: Cells encased in a 
pale yellow mucilage giving the colony a dull 
appearance. Colony surface studded with 
little humps. 

Aerobic. 



ORDER I. PSEUDOMONADALES 



Source: Activated sludge. 
Habitat: Unknown. 



Source: Activated sludge. 
Habitat: Unknown. 



2. Nitrosogloea schizobacteroides H. 

Winogradsky, 1935. (Nitrosocystis "11", H. 
Winogradsky, Trans. Third Intern. Cong. 
Soil Sci., Oxford, 1, 1935, 139; H. Winograd- 
sky, Compt. rend. Acad. Sci., Paris, 200, 
1935, 1887; Ann. Inst. Past., 58, 1937, 333.) 

schiz.o.bac.te.ro.i'des. Gr. schiza cleft, 
fission; Gr. noun bactrmn a rod; Gr. noun 
idus form, shape; M.L. adj. schizobacteroides 
shaped like a fission rod. 

Elongated rods or short filaments 3 to 4 
microns long. 

Colonies on silica gel : Flat groups of cells 
are produced which are united in a common 
sheath. The aggregates form a pseudo-tissue 
of interwoven filaments suggestive of a 
fungus pad. The pad can be removed as a 
unit from the medium. 

Aerobic. 



3. Nitrosogloea membranacea H. 

Winogradsky, 1935. (Nitrosocystis "III", H. 
Winogradsky, Trans. Third Intern. Cong. 
Soil Sci., Oxford, 1, 1935, 139; Compt. rend. 
Acad. Sci., Paris, 200, 1935, 1887; Ann. Inst. 
Past., 58, 1937, 333.) 

mem.bran.a'ce.a. L. adj. membranaceus 
membranaceous . 

Ellipsoidal cells commonly in pairs and 
also solitary. 

Colonies on silica gel: Appear as dull mu- 
coid material with a pale straw color. The 
cells are held firmly together so that the 
entire colony is easily picked up with the 
transfer needle. No structural units within 
the colony. 

Aerobic. 

Source: Activated sludge. 

Habitat: Unknown. 



Genus VI. Nitrobacter Winogradsky, 1892. 
(Arch. Sci. biol., St. Petersburg, 1, 1892, 127.) 

Ni.tro.bac'ter. Gr. noun nitrum nitre, M.L. nitrate; M.L. noun bacter the masculine 
form of the Gr. neut.n. bactrum a rod; M.L. mas.n. Nitrobacter nitrate rod. 
Cells rod-shaped. Oxidize nitrites to nitrates. 
The type species is Nitrobacter winogradshji Winslow et al. 



1. Nitrobacter winogradskyi Winslow 
et al., 1917. (Nitrobacter Winogradsky, 
Arch. Sci. biol., St. Petersburg, 1, 1892, 127; 
Bacterium nitrobacter Lehmann and Neu- 
mann, Bakt. Diag., 2 Aufl., 2, 1899, 187; 
Winslow et al.. Jour. Bact., 2, 1917, 552.) 

wi.no.grad'sky.i. Named for S. Wino- 
gradsky, the microbiologist who first iso- 
lated these bacteria; M.L. mas.gen.n. 
winogradskyi of Winogradsky. 

Description taken from Gibbs (Soil Sci., 
8, 1919, 448). 

Short, non-motile rods with gelatinous 
membrane, 0.6 to 0.8 by 1.0 to 1.2 microns. 
Do not stain readily. Gram-negative 
(Omelianski, Cent. f. Bakt., II Abt., 19, 
1907, 263). 

Can be cultivated on media free of organic 
matter. Sensitive to certain organic com- 
pounds. 

Washed agar colonies: In 7 to 10 days 



very small, light brown, circular to irregular 
colonies, becoming darker. 

Silica gel: Colonies smaller but more 
dense than those on washed agar. 

Washed agar slant: In 7 to 10 days scant, 
grayish streak. 

Inorganic solution medium: After 10 daj's 
flocculent sediment. Sensitive to ammonium 
salts under alkaline conditions. 

Nitrite is oxidized to nitrate. 

Aerobic. 

Strictly autotrophic. 

Optimum temperature, between 25° and 
28° C. 

Source: Soil. 

Habitat: Presumably widely distributed 
in soil. 

2. Nitrobacter agilis Nelson, 1931. 
(Zent. f. Bakt., II Abt., 83, 1931, 287.) 



FAMILY I. NITROBACTERACEAE 



73 



ag'il.is. L. adj. agilis agile, quick. 

Rods, 0.5 by 0.8 to 0.9 micron, occurring 
singly, sometimes in pairs or larger aggre- 
gates. Rapidly motile with a long, thin, 
polar flagellum often 7 to 10 times as long as 
the rod. (Non-motile culture obtained by 
Kingma Boltjes, Arch. f. Mikrobiol., 6, 
1935, 79.) Gram-negative. 

No growth in nutrient broth, nutrient 
agar, nutrient or plain gelatin, litmus or 
plain milk, glucose or plain yeast water, or 
on potato. 

Nitrite agar: After two weeks, produces 
semi -spherical, minute, nearly transparent 
colonies. Oxidation usually complete in 10 
to 14 days. 



Inorganic liquid medium containing ni- 
trite: Produces uniformly dispersed growth. 

Optimum pH, between 7.6 and 8.6. Limits 
of growth, 6.6 to 10.0. 

Temperature relations: Optimum for 
growth, between 25° and 30° C. Optimum 
for oxidation, 28° C. No oxidation at 37° C. 
Thermal death point, 60° C. for five min- 
utes. 

Strictly autotrophic. 

Aerobic. 

Source: Isolated from greenhouse soils 
and from sewage effluents in Madison, 
Wisconsin. 

Habitat: Presumably widely distributed 
in soil. 



Genus VII. Nitrocystis H. Winogradsky , 1935. 
(Trans. Third Intern. Cong. Soil Sci., Oxford, 1, 1935, 139.) 

Ni.tro.cyst'is. Gr. noun nitrum nitre, M.L. nitrate; Gr. noun cyslis bladder, cj'st; M.L. 
fem.n. Nitrocystis nitrate cyst. 

Cells ellipsoidal or rod-shaped. Embedded in slime and united into compact zoogloeal 
aggregates. Oxidize nitrites to nitrates. 

It has been suggested that these organisms were really myxobacters. See note under 
Nitrosocystis for references. 

The type species is Nitrocystis sarcinoides H. Winogradsky. 



1. Nitrocystis sarcinoides H. Wino- 
gradsky, 1937. {Nitrocystis B. A., H. Wino- 
gradsky, Compt. rend. Acad. Sci., Paris, 
200, 1935, 1888; also see Ann. Inst. Past., 
58, 1937, 336.) 

sar.cin.o.i'des. L. sarcina a packet; Gr. 
idus form, shape; M.L. adj. sarcinoides re- 
sembling Sarcina, a genus of bacteria. 

Small rods 0.5 by 1.0 micron. Cells ellip- 
soidal or wedge-shaped and grouped in sar- 
cina-like packets. 

Colonies on silica gel : On the surface of 
gel coated with kaolin the colonies appear 
as small, raised, amber warts. The colonies 
grow up to 5 mm in diameter. The colonies 
are viscous and sticky when young, and 
they become brown with age, shrink, and 
look like scales and become hard like grains 
of sand. Each colony is enveloped in several 
layers of a thick slime which holds the cells 
together so that the entire colony can be 
removed with a transfer needle. 

Aerobic. 

Source: Activated sludge. 

Babitat: Unknown. 



2. Nitrocystis micropunctata (H. 

Winogradsky, 1935) H. Winogradsky, 1937. 
(Nitrocystis "III", H. Winogradsky, Trans. 
Third Intern. Cong. Soil Sci., Oxford, 1, 
1935, 139; Nitrogloea micropiinctata H. 
Winogradsky, Compt. rend. Acad. Sci., 
Paris, 200, 1935, 1888; H. Winogradsky, 
Ann. Inst. Past., 58, 1937, 326.) 

mi.cro.punc.ta'ta. Gr. micrus small; L. 
punctatus spotted; M.L. adj. micropunctatus 
full of small spots. 

Cells are ellipsoidal rods, about 0.5 mi- 
cron in diameter, which stain poorly except 
at the ends. Encased in a viscous slime. 

Colonies on silica gel: Like those of A^. 
sarcinoides except that they are clearer and 
have a more plastic consistency. The cells 
are not held together by the slime in the 
colony as with N. sarcinoides. The capsule 
is more readily differentiated in old colonies. 

Aerobic. 

Source: Activated sludge. 

Habitat: Unknown. 



74 ORDER I. PSEUDOMONADALES 

FAMILY II. METHANOMONADACEAE BREED Fam. Nov.* 

(Oxydobacteriaceae Orla-Jensen, pro parte, Cent. f. Bakt., II Abt., 22, 1909, 329; 
Protohacterieae Rahn, Cent. f. Bakt., II Abt., 96, 1937, 273.) 

Me. tha.no. mo. na.da'ce.ae. M.L. noun Methanonwnas, -adis a genus of bacteria; -aceae 
ending to denote a familj^; M.L. fern. pi. n. Methanomonadaceae the Methanonwnas family. 

Rod -shaped organisms deriving their life energy from the oxidation of simple compounds 
of hydrogen or carbon. Polar flagellate when motile. Gram-negative. Found in soil and 
water. 

It is clear that the species placed in the genera in this family belong with other polar 
flagellate bacteria (the group of pseudomonads in the broad sense). Their method of de- 
riving energy from oxidative processes is in accord with that of many other polar-fiagellate 
bacteria. As a matter of convenience and as a means of emphasizing the fact that the species 
included here secure their energy from the oxidation of simple hydrogen and carbon com- 
pounds, the genera that have been proposed to include these species are grouped into a 
family separate from those of the species that secure their energy from the oxidation of 
simple nitrogen or sulfur compounds on the one hand, and those that normally secure their 
energy from the oxidation of glucose or other organic compounds on the other hand. Further 
studies of the differences in physiology found among the polar flagellate bacteria are badly 
needed. 

Key to the genera of the family Methanomonadaceae. 

I. Organisms deriving their life energy from the oxidation of simple compounds of hy- 
drogen. 

A. Cells capable of securing growth energy by the oxidation of methane. 

Genus I. Methanomonas, p. 74. 

B. Cells capable of securing growth energy by the oxidation of hydrogen. 

Genus II. Hydrogenomonas , p. 75. 
II. Organisms deriving their life energy from the oxidation of carbon monoxide. 

Genus III. Carhoxydomonas , p. 77. 

Genus I. Methanomonas Orla-Jensen, 1909. 
(Cent. f. Bakt., II Abt., 22, 1909, 311.) 

Me.tha.no.mo'nas. Gr. methy wine; Gr. methe strong drink; M.L. methanum methane; 
Gr. monas a unit, monad; M.L. fem.n. Methanomonas methane monad. 

Cells monotrichous, capable of obtaining energj' from oxidation of methane to CO2 
and water. 

The type species is Methanomonas methanica (Sohngen) Orla-Jensen. 

1. Methanomonas methanica (Sohn- motile in young cultures by means of a 

gen, 1906) Orla-Jensen, 1909. {Bacillus single flagellum. In older cultures nearly 

me/AamciiS Sohngen, Cent. f. Bakt., II Abt., spherical. Can be cultivated in an atmos- 

15, 1906, 513; Orla-Jensen, Cent. f. Bakt., phere composed of one part CH4 and two 

II Abt., ^^, 1909, 311.) parts air on washed agar containing the 

me.tha'ni.ca. M.L. noun methanum necessary inorganic salts. The growth is 

methane; M.L. adj. melhanicus relating to membranous, 

methane. At the end of two weeks, the organisms 

Short rods, 0.5 to 0.8 by 2.0 to 3.0 microns, changed an atmosphere containing 225 ml 

* Revised })y Prof. Robert S. Breed, Cornell University, Geneva, New York, January, 
1954. 



FAMILY II. METHANOMONADACEAE 75 

CH4 and 321 ml O2 to the following: In addition, 21 ml CO2 were dissolved in 

CH4 ml the liquid. 

CO2 78 ml Habitat : Presumably widely distributed 

O2 172 ml in soil. 

Genus II. Hydrogenomonas Orla-Jensen, 1909. 
(Cent. f. Bakt., II Abt., 22, 1909, 311.) 

Hj-.dro.ge.no.mo'nas. Gr. hydro water; Gr. genus race, offspring; whence, M.L. hy- 
drogenum hydrogen, that which produces water; Gr. monas a unit, monad; M.L. fem. noun 
Hydrogenomonas hydrogen monad. 

Short rods that are polar flagellate when motile. Cells capable of deriving energy from the 
oxidation of hydrogen. They may grow well on organic media without hydrogen although 
this has not been shown to be true in all cases. Gram-negative. Found in soil and water. 

This group of bacteria is characterized by the ability to grow in substrates containing no 
organic matter and to use elemental hydrogen as the source of energj^ for growth. Under 
these conditions CO2 is used as the source of carbon. Bacteria with similar phj'siological 
characteristics but differing in morpholog}' are placed in the genera Bacillus and Clos- 
tridium. Although other bacteria and even certain algae have enzyme systems which can 
activate hydrogen and reduce CO2 in the process, there is no evidence that these organisms 
are able to grow in inorganic media with hydrogen as the exclusive source of energj^ (see 
Stephenson and Strickland, Biochem. Jour., 25, 1931, 205-215; Woods, Biochem. Jour., 30, 
1936, 515; Lee and Umbreit, Zent. f. Bakt., II Abt., 101, 1940, 354; Gaffron, Amer. Jour. 
Bot., 27, 1940, 273). 

The tj'pe species is Hydrogenomonas pantotropha (Kaserer) Orla-Jensen. 

Key to the species of genus Hydrogenomonas. 

I. Not sensitive to high concentrations of O2 . 

A. When growing autotrophically, no pellicle on liquid media. 

1. Hydrogenomonas pantotropha. 

B. When growing autotrophically, pellicle formed on liquid media. 

2. Hydrogenomonas facilis. 
II. Sensitive to high concentrations of O2 . 

A. When growing autotrophically, no pellicle on liquid media. 

3. Hydrogenomonas flava . 

B. When growing autotrophically, pellicle formed on liquid media. 

4. Hydrogenomonas vitrea. 

1. Hydrogenomonas pantotropha (Ka- Inorganic solution: When cultivated 

serer, 1906) Orla-Jensen, 1909. (Bacillvs under an atmosphere of O2 , CO2 and Ho , 

paniotrophus Kaserer, Cent. f. Bakt., II the liquid becomes turbid without pellicle 

Abt., 16, 1906, 688; Orla-Jensen, Cent. f. formation. 

Bakt., II Abt., .?^, 1909, 311.) Inorganic solid media: When cultivated 

pan.to'troph.a. Gr. prefix panto all; Gr. ""^er an atmosphere of O2 , CO2 and H2 , 

, 7 r 1 TiTT J- I i I the colonies are yellow and slimy, and the 

trophus feeder; M.L. adj. pantotrophus om- , , ^ , , ,- , 

agar plates have an odor resembling hot, 

mvorous. x 

soapy water. 

Rods, 0.4 to 0.5 by 1.2 to 1.5 microns, with G^\^t\,, colonies: Yellow, smooth, rarely 

rounded ends. Occur singly, in pairs and in concentrically ringed or greenish, 

chains. Encapsulated. Actively motile by Gelatin stab: Growth only at surface. As 

means of a single, long, polar flagellum. a rule no liquefaction. 

Gram stain not recorded. Bipolar staining Agar colonies: Same as on gelatin, green- 
in old cultures. ish, often slimy. 



76 



ORDER I. PSEUDOMONADALES 



Broth: Turbid, somewhat slimy; pellicle 
occasionally produced. 

Milk: No coagulation. A yellow pellicle 
forms. Medium becomes slimy and assumes 
a dirty flesh color. 

Potato: Moist, yellow, glistening. 

Indole not produced. 

Hydrogen sulfide not produced. 

Nitrites not produced from nitrates. 

Carbohydrates not utilized. 

Aerobic. 

Optimum temperature, between 28° and 
30° C. 

Facultatively autotrophic. 

Distinctive characters: Develops auto- 
trophically in inorganic medium under an 
atmosphere of H2 , O2 and CO2 . Oxidizes 
hydrogen to water and uses CO2 as the 
source of carbon for growth. 

Source: Isolated from soil near Vienna. 

Habitat: Probably widely distributed in 
soil. 

2. Hydrogenomonas facilis Schatz and 
Bovell, 1952.* (An undescribed Hydrogeno- 
monas, Schatz, Proc. Soc. Amer. Bact., 
Baltimore Meeting, 1950, 124; Schatz and 
Bovell, Jour. Bact., 63, 1952, 87.) 

fa'ci.lis. L. Sid\.Jacilis ready, quick. 

Rods 0.3 bj^ 2.0 microns in autotrophic 
and 0.4 by 2.5 microns in heterotrophic cul- 
tures. Occur singly, in pairs and in short 
chains. Motile by means of one or two polar 
flagella. Gram-negative. 

Gelatin stab: Rapidly liquefied. 

Agar colonies: Round, raised, glistening, 
translucent, non-fluorescent and non-mu- 
coid. No distinctive odor developed. 

Autotrophic media: Cultures readily 
maintained in media of this type. 

Autotrophic gas uptake : The same overall 
reaction is effected as that carried out by 
certain anaerobically adapted green algae 
(6H2 + 2O2 + CO2 -^ CH2O + 5H2O). In an 
atmosphere of CO 2 and H2 , no CO2 fixation 
accompanies the quantitative reduction of 
nitrate to nitrite by molecular H2 ; nor is 
there any change in concenti-ation of bicar- 
bonate or in total gas pressure (Warburg 
apparatus) when acetone, pyruvate ora-ke- 



toglutarate are added (Schatz, Jour. Gen. 
Microbiol., 6, 1952, 329). 

Broth: Turbid with pellicle. 

Milk: Slowly digested with alkalinization. 

Potato: Abundant, spreading, non-pig- 
mented growth. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acetylmethylcarbinol not produced. 

Nitrites produced from nitrates. 

Aerobic, obligate. 

Non-hemolytic. 

Optimum temperature, 28° C. 

Source: Isolated from soil. 

Habitat: Presumably widely distributed 
in soil. 

3. Hydrogenomonas flava Niklewski, 
1910. (Jahrb. f. wissensch. Botanik, 48, 
1910, 113; emend. Kluyver and Manten, An- 
tonie V. Leeuwenhoek, 8, 1942, 71.) 

fla'va. L. flavus yellow. 

Rods 1.5 microns in length. Motile by 
means of polar flagella. Gram-negative. 

Agar colonies on inorganic medium in 
presence of H2 ,02andC02 : Small, smooth, 
yellow, shining, adhering to medium. De- 
velop well below surface of medium, but 
growth is paler. 

Gelatin not liquefied. 

Inorganic liquid medium in presence of 
H2 , O2 and CO2 : No pellicle formation. 
Good development when there is from 2 to 8 
per cent oxygen in the gas. At higher O2 
concentrations good growth occurs only in 
association with H. vitrea or other bacteria. 

Oxidizes hydrogen to water. 

Microaerophilic, growing in an atmos- 
phere of low oxygen tension, not exceeding 
8 per cent. 

Facultatively autotrophic. 

Distinctive characters: Found singly on 
slides whereas the rod-shaped cells of Hydro- 
genomonas vitrea tend to cling together in 
masses. Colonies on agar opaque, not trans- 
parent. 

Source: Isolated from mud, garden soil, 
pasture land, vegetable mold and peat. 

Habitat: Presumably widely distributed 
in soil. 



* Prepared by Prof. Albert Schatz, National Agricultural College, Farm School P.O., 
Bucks Co., Pennsylvania, December, 1953. 



FAMILY II. METHANOMONADACEAE 



77 



4. Hydrogenomonas vitrea Niklewski, 
1910. (Jahrb. f. wissensch. Botanik, 48, 1910, 
113.) 

vit're.a. L. vitreus of glass. 

Rods 2.0 microns in length, cells adhering 
to each other as by slime. Motility not ob- 
served. 

Agar colonies on inorganic medium in 
presence of H2 , O2 and CO2 : Delicate, 
transparent, with slight fluorescence and 
yellow center. Surface folded. Do not de- 
velop readily beneath the surface of me- 
dium. 

Agar streak on inorganic substrate : Same 
as agar colonies e.xcept that growth is 
spreading. 

Inorganic liquid medium in presence of 
H2 , O2 and CO2 : Pellicle, adherent to wall 



of tube. Good development when there is 
from 2 to 8 per cent oxygen in the gas. At 
higher O2 concentrations good growth occurs 
only in association with H. flava or other 
bacteria. 

Oxidizes hydrogen to water. 

Microaerophilic, growing in an atmos- 
phere of low oxygen tension, not exceeding 
8 per cent. 

Facultatively autotrophic. 

Distinctive characters: Grows in sub- 
strates containing no organic matter and 
produces a pellicle. 

Source: Isolated from mud, garden soil, 
pasture land, vegetable mold and peat. 

Habitat: Presumably widely distributed 
in soil. 



Gemis III. Carboxydonionas Orla-Jensen, 1909. 
(Cent. f. Bakt., II Abt., 22, 1909, 311.) 

Car.box.y.do.mo'nas. L. noun carbo charcoal, carbon; Gr. adj. oxys sharp; Gr. noun 
monas a unit, monad; M.L. fem.n. Carboxydomonas the carbon-oxidizing monad. 

Autotrophic, rod-shaped cells capable of securing growth energy by the oxidation of CO, 
forming CO2 . 

The tj^pe species is Carboxydomonas oligocarbophila (Beijerinck and van Delden) Orla- 
Jensen. 



1. Carboxydonionas oligocarbophila 

(Beijerinck and van Delden, 1903) Orla- 
Jensen, 1909. (Bacillus oligocarbophilns 
Beijerinck and van Delden, Cent. f. Bakt., 
II Abt., 10, 1903, 33; Orla-Jensen, Cent. f. 
Bakt., II Abt., 22, 1909, 311.)* 

o.li.go.car.bo'phi.la. Gr. adj. nligus 
little, scanty; L. noun carbo charcoal, car- 
bon; Gr. adj. ■philus loving; M.L. adj. oligo- 
carbophilus loving little carbon. 

Rods very small, 0.5 by 1.0 micron, color- 
less, united into irregular masses by a 
slimy substance. Non-motile. There is little 
cytoplasm within the slimy, cellulose-like 
wall of the cells. 



Growth occurs in culture fluids free from 
organic matter and on washed agar con- 
taining the necessarj^ inorganic salts. 

Media containing carbonaceous materials : 
No growth. 

Liquid media: A thick, slimy film is pro- 
duced. 

CO is utilized as food and as such is oxi- 
dized to CO 2 • In symbiosis with other bac- 
teria, hj'drogen in water is o.xidized by the 
catalytic reduction of CO2 to CO. The CO is 
then metabolized, again forming CO2 (Ka- 
serer. Cent. f. Bakt., II Abt., 16, 1906, 681). 

Growth best in the dark. 

Optimum temperature, 25° C. 



* Kistner (Proc. Kon. Nederl. Akad. van Wetenschappen, Amsterdam, Series C, 56, 
1953, 443) , in a paper received after the section covering Carboxydomonas was prepared , ques- 
tions the data gathered by Beijerinck, Kaserer, Lantzsch and others. He concluded that 
their reports were based on doubtful and imperfect ol)servations. Using a carefully con- 
trolled technique, he was able to isolate an organism which oxidized CO to CO2 and which 
had the characters of a pseudomonad (polar flagellate, straight rod). On further testing, 
however, because it also oxidized H2 , he concluded that it belonged in the genus Hydro- 
genomonas. Further studies on the species are promised. 



78 ORDER I. PSEUDOMONADALES 

Discussion : In spite of the fact that reaction would be helpful in clarifying this 

several able bacteriologists have studied situation. If the species is to be accepted as 

this species and the actinomycete that has a non-motile but related to polar-flagellate 

similar physiology, several important points bacteria, it must be Gram-negative. If an 



actinomycete, it would be Gram -positive. 
Lantzsch reports the organism he studied 



are left in doubt; the most important of 

these is whether Beijerinck was right ii 

thinking the actinomycete something dis , , . , ,. , ^ , , ^ 

^. . r \- T> 11 T h i,-i „>. (which was an actinomj^cete) to be Gram- 

tinct from his Bacillus ohgocarbophilus, or ^ j / 

whether Lantzsch (Cent. f. Bakt., II Abt., Positive. 

57, 1922, 309) was right in thinking of them as Source: Isolated from garden soil. 

but stages in the growth cycle of a single Habitat: Presumably widely distributed 

species. Definite data in regard to the Gram in soil. 



FAMILY III. THIOBACTERIACEAE JANKE, 1924.* 

(Allgem. Tech. Mikrobiol., Dresden and Leipzig, I Teil, 1924, 68.) 

Thi.o.bac.te.ri.a'ce.ae. M.L. neut.n. Thiobacterium type genus of the family; -aceae 
ending to denote a family; M.L. fem.pl.n. Thiobacteriaceae the Thiobacterium family. 

Coccoid, straight or curved rod-shaped bacteria. Oxidize sulfur compounds, usually de- 
positing free sulfur granules within or without the cells. Never filamentous. Colorless sulfur 
bacteria that are sometimes embedded in gelatinous pellicles or in gelatinous bladder-like 
colonies. Polar flagellate when motile. Presumably Gram-negative. Found in places where 
hydrogen sulfide occurs or may oxidize free sulfur, thiosulfates or related compounds. 

While all of the species placed in this family have been described as colorless sulfur bac- 
teria, they are still inadequately known and may not all deserve to be designated as sulfur 
bacteria. It is hoped that placing them together in one family will cause comparative studies 
to be made. 

The type genus is Thiobacterium Janke. 

Key to the genera of family Thiobacteriaceae. 
I. Free sulfur granules deposited within or without the cells. Usually found in sulfurous 
waters or soil. 

A. Cells coccoid or straight rods. 

1. Non-motile so far as known. ^ 

Genus I. Thiobacterium, p. 79. 

2. Motile by means of polar flagella so far as known. 

a. Cells rod-shaped, very large. 

Genus II. Macromonas, p. 80. 
aa. Cells round to ovoid, large. 

Genus III. Thiovuhim., p. 81. 

B. Cells large, curved rods, somewhat pointed. 

Genus IV. Thiospira, p. 82. 
II. Oxidize free sulfur, thiosulfates and related sulfur compounds to sulfates. Autotrophic 
or facultatively autotrophic. 

Genus V. Thiohacillus, p. 83. 

* Revision of Thiobacteriaceae Janke prepared by Prof. Dr. Alexander Janke, Technische 
Hochschule, Vienna, Austria, December, 1954, with the assistance of Prof. Robert S. Breed, 
Cornell University, Geneva, New York. 



FAMILY III. THIOBACTERIACEAE 



79 



Genus I. Thiobacterium Janke, 1924* 

(Janke, Allgem. Tech. Mikrobiol., I Teil, 1924, 68; not Thiobacterium Issatchenko and 

Salimowskaja, Zur Morphologie u. Physiol, der Thionsaurebakterien (Russian), 

Izyiestia Gosud. Gidrobiol. Inst. (Memoirs State Hydrobiol. Inst. 

Leningrad), No. 21, 1928, 61.) 

Thi.o.bac.te'ri.um. Gr. noun thi iwi suUur; Gr. dim. noun bacterium a small rod; M.L. 
neut.n. Thiobacterium small sulfur rod. 

Rod-shaped, sulfur bacteria found in fresh or salt water or soil. Cells 1.0 micron or less 
in diameter. Motility not observed. Sulfur granules sometimes found inside, sometimes 
outside the cells. These cells may or may not be embedded in pellicles or in spherical, 
bladder-like colonies. 

The type species is Thiobacterium bovista Janke. 

Key to the species in genus Thiobacterium. 

I. Sulfur grains are found within the cells. Forms colonies in bladder-like masses which 
resemble puff balls. 

1. Thiobacterium bovista. 
II. Sulfur grains are found outside of the cells. 

A. Produces colonies on the surface of water containing proper nutrients. Sulfur crys- 
tals are found among the cells. 

2. Thiobacterium cristalliferum. 

B. Produces a surface film in the form of a network on water. Sulfur globules are found 
among the cells. 

3. Thiobacterium retiformans. 



1. Thiobacterium bovista (Molisch, 
1912) Janke, 1924. {Bacterium bovista Mo- 
lisch, Cent. f. Bakt., II Abt., 33, 1912, 59; 
Janke, Allgem. Tech. Mikrobiol., I Teil, 
1924, 68.) 

bo.vis'ta. M.L. noun Bovista a genus of 
puff balls; from German bovist puff ball; 
M.L. fem.n. bovista puff ball. 

Rod-shaped bacteria embedded in the 
wall of bladder-like gelatinous colonies, the 
interiors of which are filled with a clear 
liquid. The cells are 0.6 to 1.5 by 2.0 to 5.0 
microns, occurring by the thousands in 
each colony. Each cell contains from one to 
four sulfur granules. No motility observed. 
The cells stain well with gentian violet while 
the gelatinous matrix stains poorly, if at all. 

The spherical colonies increase in number 
by a kind of budding process that produces 
smaller colonies. The colonies are white by 
reflected light, black or bluish black by 
transmitted light. Groups of these colonies 
have the appearance of groups of puff balls 



of variable sizes. They occur near the surface 
of the water. 

These organisms have not been cultivated 
in pure culture. 

Source: Found commonly in sulfurous 
sea-water in the harbor at Trieste. 

Habitat: Presumably widely distributed 
in coastal waters containing hydrogen sul- 
fide. 

2. Thiobacterium cristalliferum (Gickl- 
horn, 1920) Janke, 1924. (Bacterium cris' 
talliferum Gicklhorn, Cent. f. Bakt., II Abt., 
50, 1920, 420; Janke, Allgem. Tech. Mikro- 
biol., I Teil, 1924, 68.) 

cris. tal.li'fe. rum. Gr. noun crystallus a 
crystal; L. v.fero to bear; M.L. adj. cristal- 
liferus crystal-bearing. 

Straight to curved, rod-shaped bacteria. 
0.3 to 0.5 by 1.0 to 2.4 microns. Deposit sul- 
fur crystals outside of the cells. Non-motile. 
Stain readily in gentian violet. 

Colonies developed on the surface of water 



* Prepared by Prof. Dr. Alexander Janke, Technische Hochschule, Vienna, Austria, 
December, 1954. 



80 



ORDER I. PSEUDOMONADALES 



containing potassium sulfide (K2S) which 
was inoculated with a handful of garden soil 
from Graz, Austria. At the end of three 
weeks, numerous, snow-white colonies de- 
veloped on the surface of the water. 

Colonies which at first are of microscopic 
size maj^ become 0.8 to 1.5 mm in diameter. 
Sulfur crystals appear by transmitted light 
as a black mass in the center of the smaller 
colonies, but these crystals extend to the 
margin in older colonies. 

Habitat: Garden soil. 

3. Thiobacteriuni retifornians (Gickl- 
horn, 1920) Janke, 1924. (Bacterium retifor- 
nians Gicklhorn, Cent. f. Bakt., II Abt., 50, 
1920, 421; Janke, Allgem. Tech. Mikrobiol., 
I Teil., 1924, 68.) 



re. ti. for 'mans. L. noun rete a net; L. v 
formo to form; M.L. part. adj. retifonnans 
net-forming. 

Rod-shaped bacteria, 0.5 to 1.0 by 2.0 to 
4.5 microns. Globular sulfur granules found 
among the cells. Non-motile. Forms pelli- 
cles and zoogloeal masses. 

Developed in water containing potassium 
sulfide (K2S) which was inoculated with the 
decaying roots of nettle plants. This species 
developed a delicate pellicle in the form of a 
network on the surface of the water. It 
also formed zoogloeal masses attached to 
the wall of the culture flask. 

Source: Soil containing decaying roots, 
Graz, Austria. 

Habitat: Presumably widely distributed. 



Gemis II. Macromonas Utermohl and Koppe, 1923.* 

(Utermohl and Koppe, Verhandl. Intern. Ver. f. Theoret. u. angew. Limnologie, 1923, 86; 
Thiovibrio Janke, Allgem. Tech. Mikrobiol., I Teil, 1924, 68.) 

Mac.ro.mo'nas. Gr. adj. macrus large; Gr. noun monas a unit, monad; M.L. fem.n. Macro- 
monas a large monad. 

Colorless, cylindrical to bean -shaped bacteria, actively motile by means of a single polar 
flagellum. Cells large, 3.0 to 14.0 microns in diameter. Multiplication by constriction (fis- 
sion). Chiefly characterized by the occurrence of calcium carbonate inclusions in the form 
of large spherules. In their natural habitat they may also contain small sulfur globules. 

Two species have been distinguished, primarily on the basis of cell size. Whether this is 
sufficiently constant to serve as a specific character has not been definitely established. 
From studies on the organisms in their natural habitat, which are still limited in scope and 
extent, it appears at present that the two species should be maintained, at least provi- 
sionally. It is possible, however, that further observations, especially with cultures under 
different environmental conditions, will show the occurrence of intermediate types and of a 
greater range of variation in size of pure cultures than has previously been reported. 

The type species is Macromonas mobilis (Lauterborn) Utermohl and Koppe. 

Key to the species of genus Macromonas. 

I. Cells measure 12 microns or more in length and 8 microns or more in width. 

1. Macromonas mobilis. 

II. Cells measure less than 12 microns in length and 5 microns or less in width. 

2. Macromonas bipunctata. 



1. Macromonas mobilis (Lauterborn, 
1915) Utermohl and Koppe, 1923. {Achro- 
matiitm mobile Lauterborn, Verhandl. 
Naturhist.-medizin. Vereins, Heidelberg, 
N. F., IS, 1915, 413; Utermohl and Koppe, 



Verhandl. Intern. Ver. f. theoret. u. angew. 
Limnologie, 1923, 86 and Utermohl and 
Koppe, Arch. f. Hydrobiol., Suppl. Bd. 5, 
1925, 234.) 
mo'bi.lis. L. adj. mobilis movable, motile. 



* Prepared by Prof. Dr. Alexander Janke, Technische Hochschule, Vienna, Austi 
December, 1954. 



FAMILY III. THIOBACTERIACEAE 



81 



Colorless sulfur bacteria always occurring 
singly; slightly curved, elongated ellipsoids 
or cylinders with broad, hemispherical ends. 
Width varies from 8 to 14 microns, length 
from 12 to 30 microns; most common size, 9 
by 20 microns. Multiplication by constric- 
tion in the middle. 

Cells actively motile by means of a single 
polar flagellum distinctly visible without 
special staining. It is 20 to 40 microns long, 
and, with respect to the direction of mo- 
tion, always posteriorly placed. Rate of 
movement somewhat sluggish, about 800 
microns per minute, probably on account 
of the high specific gravity of the cells. 

Normally contain small sulfur droplets 
and, in addition, large, roughly spherical 
inclusions of calcium carbonate. Two to 
four such crystal masses almost fill a single 
cell. Under unfavorable conditions the 
calcium carbonate crystals may disappear 
before the sulfur globules. 

Microaerophilic; apparently require hy- 
drogen sulfide. 

Habitat: Found in fresh-water environ- 
ments containing sulfide and calcium ions, 
as in shallow basins and streams in the upper 
layers of the mud. 

2. Macromonas bipunctata (Gicklhorn, 
1920) Utermohl and Koppe, 1925. (Pseudo- 
nonas bipunctata Gicklhorn, Cent. f. Bakt., 
[I Abt., 50, 1920, 425; Utermohl and Koppe, 
A.rch. f. Hydrobiol., Suppl. Bd. 5, 1925, 235.) 

bi.punc.ta'ta. L. bis twice; L. part. adj. 
punctatus punctate, dotted; M.L. adj. bi- 
punctatiis twice punctate. 



Cells colorless, occurring singly; cylindri- 
cal with hemispherical ends, after cell divi- 
sion often temporarily pear-shaped. 3 to 5 
by 8 to 12 microns. Multiplication by con- 
striction in the middle. 

Actively motile by means of a single polar 
flagellum, about 10 to 15 microns long, al- 
ways posteriorlj^ placed with respect to the 
direction of movement. Flagellum delicate, 
not visible without staining. Rate of move- 
ment sluggish, about 600 microns per min- 
ute. Probably this slow motion is due to the 
high specific gravity of the cells. 

Normally contain calcium carbonate 
crystals as inclusions. These are in the form 
of large spherules, one or two of which 
nearly fill the individual cells. Sulfur glo- 
bules have not been demonstrated with 
certainty as yet. 

Microaerophilic, but it is uncertain 
whether hj^drogen sulfide is required. 

A second species that is like Macromonas 
bipunctata, except that the cells are smaller 
in size, has been named by Gicklhorn (op. 
cit., 50, 1920, 425). Pure-culture studies may 
show the two species to be identical as dif- 
ference in size of cells has not been found to 
be significant elsewhere among sulfur bac- 
tei'ia. 

Source: From stems, leaves, etc. of fresh- 
water plants in ponds near Graz, Austria. 

Habitat: Found in fresh-water environ- 
ments containing calcium ions; but it has 
been found in sulfide-containing as well as 
in sulfide-free water. Also found in shallow 
basins and streams in upper layers of the 
mud. 



Genus III. Thiovulum Hinze, 1913.* 
(Ber. d. deutsch. bot. Ges., 31, 1913, 195.) 

Thi.o'vu.lum. Gr. noun thium sulfur; L. noun ovum egg; M.L. neut.dim.n. Thiovulum 
small sulfur egg. 

Unicellular organisms, round to ovoid, 5.0 to 20.0 microns in diameter. Cytoplasm often 
concentrated at one end of the cell, the remaining space being occupied by a large vacuole. 
Multiplication by constriction which, in late stages, merges into fission. Actively motile; 
movements accompanied by rapid rotation. Flagellation not definitely demonstrated, but 
type of locomotion suggests polar flagellation. Normally contain sulfur globules in the cj^to- 
plasm; hence, these are frequently concentrated at one end of the cell. 

It is difficult to establish distinct species. Those that have been described differ only in 

* Prepared by Prof. Dr. Alexander Janke, Technische Hochschule, Vienna, Austria, De- 
cember, 1954. 



82 



ORDER I. PSEUDOMONADALES 



size, and the differences appear to be far from constant. The ovoid cells of Thiovulum majiis 
are noted as being 11 to 18 microns long and 9 to 17 microns wide, while Thiovulum minus 
comprises the smaller forms from 9.6 to 11.0 microns long by 7.2 to 9.0 microns wide. In 
view of the regular occurrence of all intermediate sizes, it seems best to recognize only a 
single species at present. 
The type species is Thiovulum majus Hinze. 



1. Thiovulum majus Hinze, 1913. 
(Hinze, Ber. d. deutsch. bot. Ges., 31, 1913, 
195; including Thiovulum minus Hinze, 
loc. cit.; Thiovulum muUeri Lauterborn, 
Verhandl. Naturhist.-medizin. Vereins, 
Heidelberg, N. F., 13, 1915, 414.) 

ma 'jus. L. comp.adj. major larger. 

Unicellular organisms, spherical to ovoid. 
Cytoplasm often concentrated at one end 
of the cell, the remainder being occupied by 
a vacuole. Multiplication by constriction 
which, in late stages, merges into fission. 
Size of cells, 5 to 20 microns in diameter. 

The most characteristic feature is its mo- 
tility; it is the only one of the spherical to 



ovoid, colorless sulfur bacteria capable of 
rapid movement. Flagellation has not been 
definitely demonstrated, but the type of 
locomotion suggests the presence of polar 
flagella. 

Normally contains sulfur droplets in cyto- 
plasm, frequently concentrated at one end 
of cell. 

Microaerophilic ; apparently' requires hj^- 
drogen sulfide. 

Habitat: Found in sulfide-containing 
water, usually accumulating near the sur- 
face. Often found in cultures of decaying 
algae and in both fresh-water and marine 
environments. 



Genus IV. Thiospira Vislouch, 1914* 

(Vislouch, Jour, de Microbiologic, 1, 1914, 50; Sulfospirillum Kluyver and van Niel, Zent. 

f. Bakt., II Abt., 94, 1936, 396; Thiospirillum Janke, Allgem. Tech. Mikrobiol., I Teil, 
1924, 68; not Thiospirillum Winogradsky, Schwefelbakterien, Leipzig, 1888, 104.) 

Thi.o.spi'ra. Gr. noun thium sulfur; Gr. noun spira a coil; M.L. fem.n. Thiospira sulfur 
coil or spiral. 

Colorless, motile, slightly bent, large rods, somewhat pointed at the ends, with granules 
of sulfur within the cells and a small number of flagella at the ends. 

The type species is Thiospira winogradskyi (Omelianski) Vislouch. 

Key to the species of genus Thiospira. 

I. Large spirilla containing numerous sulfur granules. 

1. Thiospira winogradskyi. 

II. Clear center of spirilla cells contains two, occasionally one or three, sulfur granules. 

2. Thiospira bipunctata. 



1. Thiospira winogradskyi (Omelian- 
ski, 1905) Vislouch, 1914. (Thiospirillum 
winogradskyi Omelianski, Cent. f. Bakt., II 
Abt., 14, 1905, 769; Vislouch, Jour, de Mi- 
crobiologic (Russian), 1, 1914, 50.) 

wi.no.grad'sky.i. M.L. gen. noun wino- 
gradskyi of Winogradsky; named for S. N. 
Winogradsky, a Russian bacteriologist. 

Large sulfur spirilla, somewhat pointed at 
the ends, 2.0 to 2.5 by 50 microns. Numerous 



granules of sulfur. Very motile, with one to 
two polar flagella. 

The large, very active sulfur spirillum 
found by Gicklhorn (Cent. f. Bakt., II Abt., 
50, 1920, 418) may have belonged to this 
species. 

Habitat: Curative mud. 

2. Thiospira bipunctata (Molisch, 1912) 
Vislouch. 1914. (Svirillum bivunctatum 



. Thiospira bipunctata (Molisch, 1912) 
louch, 1914. {Spirillum bipunctatum 



* Prepared by Prof . Dr. Alexander Janke, Technische Hochschule, Vienna, Austria, De- 
cember, 1954. 



FAMILY III. THIOBACTERIACEAE 83 

Molisch, Cent. f. Bakt., II Abt., 33, 1912, of the cell). Both ends are more or less filled 
55; Vislouch, Jour, de Microbiologie (Riis- ^vith large volutin (metachromatic) gran- 



sian),/, 1914,50.) 

bi.punc.ta'ta. L. bis twice; L. noun 
punctum a point, spot; M.L. adj. bipunc- 
tatus two-spotted 



ules. Several minute granules of sulfur are 
present in the clear center and sometimes at 
the ends. Old cells possess one flagellum at 



Small, slightly bent sulfur spirilla, mark- each end; young cells have a flagellum at one 
edly pointed at the ends; 6.6 to 14 microns end. 
long, 1.7 to 2.4 microns wide (in the center Habitat: Sea and salt waters. 

Genus V. Thiobacillus Beijerinck, 1904* 

(Beijerinck, Cent. f. Bakt., II Abt., 11, 1904, 593; not Thiobacillus Ellis, Sulphur Bacteria, 
London, 1932, 130; Sulfomonas Orla-Jensen, Cent. f. Bakt., II Abt., 22, 1909, 314.) 

Thi.o.ba.cil'lus. Gr. noun^ium sulfur; L. noun bacillus a small rod; M.L. mas.n. Thio- 
bacillus a sulfur rodlet. 

Small, Gram-negative, rod-shaped cells. Non-motile or motile, usually by means of a 
single polar flagellum. Energy derived from the oxidation of incompletely oxidized sulfur 
compounds, principally from elemental sulfur and thiosulfate but in some cases also from 
sulfide, sulfite and polythionates. The principal product of oxidation is sulfate, but sulfur 
is sometimes formed. Grow under acid or alkaline conditions and derive carbon from carbon 
dioxide or from bicarbonates in solution; some are obligate and some facultatively auto- 
trophic. Some species are anaerobic in the presence of nitrate. Found in soil, mine waste- 
waters, sewage, effluents and related sources. 

The type species of this genus is strictly autotrophic as are the majority of the species in 
the genus. It has been suggested that Thiobacillus should be restricted to these autotrophic 
species and that the facultatively autotrophic species be placed in the genus Psexidomonas. 
Some heterotrophic species now placed in Pseudomonas are known to have the ability to oxi- 
dize thiosulfates (Starkey, Soil Sci., 89, 1935, 325). 

The type species is Thiobacillus thioparus Beijerinck. 

Key to the species of genus Thiobacillus. 

I. Thiosulfate oxidized with increa.sed acidity. 

A. Tetrathionate not formed as an intermediate product. 

1. Strictly autotrophic. 

a. Does not oxidize ferrous salts. 

1. Thiobacilhis thioparus. 
aa. Oxidizes ferrous salts. 

2. Thiobacillus ferrooxidans . 

2. Facultatively autotrophic. 

a. Aerobic. 

b. Does not oxidize free sulfur. 

3. Thiobacillus novellus. 
bb. Oxidizes free sulfur to sulfate. 

4. Thiobacillus coproliticus . 
aa. Facultatively anaerobic in presence of nitrate. 

5. Thiobacillus denitrificans . 

B. Tetrathionate formed as intermediate product. 
1. Final pH, 3.0. 

6. Thiobacillus neopoUtanus. 

* Revised by Dr. C. D. Parker, South Melbourne, Australia, with the assistance of Dr. 
Kenneth L. Temple, Morgantown, West Virginia, June, 1954. 



84 



ORDER I. PSEUDOMONADALES 



2. Final pH, 1.0 or less, 
a. Nitrate utilized. 

7. Thiohacilhis concretivonis. 
aa. Nitrate not utilized. 

8. Thiobacillus thiooxidans . 
II. Thiosulfate oxidized with increased alkalinity. 

9. Thiobacillus trautweinii. 



1. Thiobacillus thioparus Beijerinck, 
1904. (Arch. d. Sci. Exact, et Nat. Haar- 
lem, Ser. 2, 9, 1904, 153; also see Cent. f. 
Bakt., II Abt., 11, 1904, 593.) 

thi.o'par.us. Gr. noun thium sulfur; L.v. 
paro to produce; M.L. adj. thioparus sulfur- 
producing. 

Thin, short rods, 0.5 by 1.0 to 3.0 microns, 
averaging 0.5 by 1.7 microns. Motile. 
Starkey (Soil Sci., 39, 1935, 209) reports the 
isolation of cultures (C) that he regards as 
practically identical with this species 
though they were non-motile and of coccoid 
form. Gram-negative. 

Thiosulfate liquid medium: Pellicle con- 
sists of cells and free sulfur. Medium be- 
comes turbid. pH drops to 4.5. 

Thiosulfate agar colonies: Small (1 to 2 
mm in diameter) circular, whitish yellow due 
to precipitated sulfur. Turn brown in old 
cultures. 

No growth on organic media. 

Optimum reaction, close to neutrality. 
Growth occurs between pH 7.8 and 4.5. 

Strictly autotrophic. Derives its energy 
by the oxidation of thiosulfate to sulfate 
and sulfur without the intermediate forma- 
tion of tetrathionate. Also oxidizes ele- 
mental sulfur. Does not oxidize hydrogen 
sulfide or sulfides. 

Utilizes nitrate and ammonium salts as 
sources of nitrogen. 

Aerobic. 

Source: Canal water, mud and soil. 

Habitat: Presumably widely distributed. 

2. Thiobacillus ferrooxidans Temple 
and Colmer, 1951. (Iron oxidizing bacter- 
ium, Colmer, Temple and Hinkle, Jour. 
Bact., 59, 1950, 317; Temple and Colmer, 
Jour. Bact.,6^, 1951,605.) 

fer.ro.o'xi.dans. L. noun Jerrum iron; 
Gr. adj. oxys sharp, acid; M.L. v. oxido to 



oxidize or make acid; M.L. part. adj. Jer- 
rooxidans iron-oxidizing. 

Description prepared by Dr. Kenneth L. 
Temple, Morgantown, West Virginia. 

Short rods, 0.5 by 1.0 micron, with rounded 
ends. Occur singly or in pairs, rarely in 
chains. Motile, presumably polar flagel- 
late. Gram -negative. 

Thiosulfate agar colonies: Very thin and 
small with irregular margins, becoming 
whitish in center upon aging. 

Thiosulfate liquid medium: Uniform tur- 
bidity; delicate pellicle in two or three 
weeks. 

Ferrous agar: Colonial appearance varies 
with ferrous-iron content of agar: on low to 
moderate iron concentration, an amber zone 
reveals the presence of microscopic colonies 
which become lobed and coated with hy- 
drated ferric oxide; on high ferrous iron 
concentration, growth is abundant becom- 
ing heavily encrusted with hydrated ferric 
oxide. 

Ferrous liquid medium: Clear, rapidly 
turning amber to reddish brown due to pro- 
duction of ferric iron; ferric hydrate pre- 
cipitated. Pellicle composed of cells and 
ferric hydrate. 

Nitrogen sources: Utilizes ammonia; ni- 
trate to a lesser extent. 

Aerobic. 

Optimum pH, between 2.5 and 5.8. No 
growth above pH 6.0. There is some step- 
wise adaptation to a lower pH than 2.5. 

Strictly autotrophic, deriving its energy 
from the oxidation of thiosulfates or inor- 
ganic ferrous iron. Sulfur not appreciably 
utilized. 

Distinctive characters: The pH range ap- 
proaches that of Thiobacillus thiooxidans but 
does not extend below pH 2.0, and elemental 
sulfur is not appreciably used. Thiosulfate 
is oxidized rapidly but both liquid and agar 



FAMILY III. THIOBACTERIACEAE 



85 



cultures differ in appearance from Thio- 
bacillus thioparus. Ferrous iron serves as a 
sufficient energy source with the concomi- 
tant formation of enormous quantities of 
ferric ions in acid media where ferric iron is 
not otherwise produced in quantity. The 
lobed, iron-encrusted colony formed on 
ferrous agar is unique. Cultures maintained 
on ferrous media lose the ability to oxidize 
thiosulfate, but colonies maintained on 
thiosulfate media retain their iron-oxidiz- 
ing capacity. 

Source: Isolated from bituminous coal 
mine drainage waters which were strongly 
acid and high in ferrous iron. Found in 
West Virginia and Pennsylvania. 

Habitat : Acid waters of high iron content 
including drainage from several types of 
mines and soils containing pyrite or marca- 
site. 

3. Thiobacillus novellus Starkey, 
1934. (Jour. Bact., 28, 1934, 365; Jour. Gen. 
Physiol., 18, 1935, 325; Soil Sci., 39, 1935, 
207, 210.) 

no.vel'lus. L. dim. adj. novellus new. 

Short rods or ellipsoidal cells 0.4 to 0.8 
by 0.6 to 1.8 microns. Non-motile. Gram- 
negative. 

Gelatin stab: Mucoid growth at point of 
inoculation. Sub-surface growth meager, 
slow liquefaction. 

Agar plate : Growth slow, colorless, moist, 
raised, circular, 1 mm in diameter. Deep 
colonies tiny, lens-shaped. 

Thiosulfate agar plate: Growth slow, be- 
coming white from precipitated sulfur. 
Surface colonies small, circular, moist. 
Crystals of CaS04 appear throughout the 
agar. 

Agar slant: Growth fairly abundant, soft, 
somewhat ropy, raised, shining, moderately 
spreading; whitish in reflected light, brown- 
ish opalescence in transmitted light. 

Thiosulfate agar slant: Growth very thin, 
practically colorless. No sub-surface 
growth. Sulfur usually precipitated as 
white, frosty film on the surface. 

Agar stab : White to cream-colored growth 
confined close to point of inoculation; pene- 
trates to bottom of tube. 



Thiosulfate agar stab: No appreciable 
surface growth. 

Broth: Slightly turbid. Gelatinous pel- 
licle. Forms long, streamer-like network 
extending from surface to the bottom. Some 
sediment. 

Thiosulfate broth: Uniform turbidity. No 
pellicle. Whitish sediment with thin, incom- 
plete membrane on the bottom of the flask. 
Reaction acid in a few days, changes pH 7.8 
to 5.8 with decomposition of a small quantity 
of thiosulfate. 

Sulfur solution medium of slightly alka- 
line reaction: No growth. 

Potato slant: Growth limited, cream- 
colored, moist, shining, slightly brown. 

Litmus milk: Slow development of slight 
alkalinity. 

Facultatively autotrophic. 

Optimum reaction: Close to neutrality 
(limiting reactions, pH 5.0 to 9.0). 

Aerobic. 

Distinctive characters: Oxidizes thiosul- 
fate to sulfate and sulfuric acid. Does not 
oxidize free sulfur. 

Source: Isolated from soils. 

Habitat: Soils. 

4. Thiobacillus coproliticus Lipman 
and McLees, 1940. (Soil Sci., 50, 1940, 432.) 

co.pro.Iit'i.cus. Gr. noun coprus dung; 
Gr. noun lithus a stone; whence coprolite, a 
fossil dung; M.L. adj . coproliticus of a copro- 
lite. 

Long, thin rods 0.1 to 0.2 by 6 to 8 (may 
measure 3 to 40) microns. Straight, S-shaped 
and curved cells. Motile by means of a sin- 
gle polar flagellum. 

Peptone soil extract agar: Slight growth. 

Nutrient broth: Little or no growth. 

Thiosulfate agar: Slow development. Pro- 
duces small, watery colonies raised above 
the agar surface. Colonies have been noted 
which were white from precipitated sulfur. 

Thiosulfate broth: Thiosulfate is oxi- 
dized. Little or no turbidity. No pellicle. 
No sediment. Change in reaction from pH 
7.6 to 6.1. 

Sulfur broth: Sulfur is oxidized. No tur- 
bidity. 

Facultatively autotrophic. 

Aerobic. 



86 



ORDER I. PSEUDOMONADALES 



Distinctive characters: Develops in inor- 
ganic media and oxidizes thiosulfate and 
sulfur to sulfate. Media with slightly alka- 
line reactions most favorable for growth. 

Source: Isolated from coprolite rock ma- 
terial from Triassic period (Arizona). 

Habitat: Unknown. 

5. Thiobacillus denitrificans Beijer- 
inck, 1904. (Beijerinck, Cent. f. Bakt., II 
Abt., 11, 1904, 597; Sulfomonas denitrificans 
Orla-Jensen, Cent. f. Bakt., II Abt., 22, 
1909, 314.) 

de.ni.tri'fi.cans. L. pref. de off, removed; 
M.L. noun niter saltpeter, nitrate; M.L. v. 
nitrifico to make nitrate, to nitrify; M.L. 
denitrifico to denitrify; M.L. part. adj. de- 
nitrificans denitrifying. 

Short rods, 0.5 by 1 to 3 microns. Motile 
by means of a single polar flagellum (Tjulpa- 
nova-Mossevitch, Arch. d. Sci. Biol., 
U.S.S.R.,SO, 1930, 203). 

Inorganic broth: Growth with production 
of gas, predominantly nitrogen. 

Thiosulfate agar colonies: Thin; clear or 
weakly opalescent. 

Optimum reaction: Neutral or slightly 
alkaline. 

Autotrophic, utilizing carbon from COo , 
carbonates and bicarbonates. Considered to 
be strictly autotrophic by Lieske (Ber. d. 
deutsch. botan. Gesell., 30, 1912, 12) and 
facultatively by Tjulpanova-Mossevitch (op. 
cit., 30, 1930, 203). Beijerinck stated (Kon. 
Akad. V. Wetenschappen Amsterdam, 42, 
1920, 899) that whereas the organism de- 
veloped initially in an inorganic medium, it 
lost the autotrophic habit bj^ cultivation in 
an organic medium. 

Facultatively anaerobic. Can live in the 
absence of free O2 in the presence of nitrate. 

Distinctive characters: Oxidizes thiosul- 
fate to sulfate under anaerobic conditions 
using nitrate as the hydrogen acceptor which 
is reduced to N2 . Also oxidizes sulfide, ele- 
mental sulfur and dithionate. 

Habitat: Canal and river water, salt 
water, soil, peat, composts and mud. 

6. Thiobacillus neapolitanus Parker, 
nom. nov. (Neue Gruppe von Schwefelbak- 
terium, Nathansohn, Mitt. Zool. Sta., 
Neapel, 15, 1902, 655; Thiobacillus X, 
Parker, Jour. Gen. Microbiol., 8, 1953, 344.) 



ne.a.po.li.ta'nus. L. adj. neapolitanus 
pertaining to Naples. 

Short rods, 0.5 by 1.0 to 1.5 microns. Non- 
motile. Gram-negative. 

Thiosulfate agar colonies: Small (1 to 2 
mm in diam.) circular, convex; whitish yel- 
low due to precipitated sulfur. 

Thiosulfate liquid medium; Uniform tur- 
bidity with pellicle which contains free 
sulfur. pH drops to 3.0. 

Sulfur liquid medium: Very slight, uni- 
form turbidity. 

Optimum pH, about 6.0; growth occurs 
between pH 8.5 to 3.0. 

Temperature relations: Optimum, 28° C; 
slow growth at 10° and 37° C; death occurs 
at 55° C. 

Strictly autotrophic. Derives energy by 
the oxidation of thiosulfate, tetrathionate, 
elemental sulfur and hydrogen sulfide. 
Thiosulfate is oxidized to tetrathionate, 
sulfate and sulfuric acid; tetrathionate is 
oxidized to sulfate and sulfuric acid while 
free sulfuric acid only is formed from ele- 
mental sulfur and hydrogen sulfide. Utilizes 
atmospheric CO 2 as a source of carbon. 
• Nitrogen sources: Ammonium; nitrate- 
and nitrite-nitrogen. 

Aerobic. 

Comments: It has not been clear until re- 
cently (Parker, Jour. Gen. Microbiol., 8, 
1953, 344) that this organism is a species 
separate from Thiobacillus thioparus Beijer- 
inck. The isolation and detailed study of an 
organism from concrete identical in most 
respects with Nathansohn 's description of 
his isolate but different from Beijerinck's 
and Starkey's description of Thiobacillus 
thioparus makes it clear that two separate 
species are involved. Thiobacillus neapoli- 
tanus produces tetrathionate and sulfate 
from thiosulfate and oxidizes HoS and tetra- 
thionate whereas Thiobacillus thioparus 
produces sulfur and sulfate from thiosulfate 
and does not oxidize H2S or tetrathionate. 

Source: Originally isolated by Nathan- 
sohn from sea water at Naples, Italy. Iso- 
lated by Parker from early stages of the cor- 
rosion of concrete sewers and other concrete 
structures. 

Habitat: Presumably widely distributed 
in soil and water, including sea water. 

7. Thiobacillus concretivorus Parker, 



FAMILY III. THIOBACTERIACEAE 



87 



1945. (Austral. Jour. Exper. Biol, and Med. 
Sci., S3, 1945, 81; also see Jour. Gen. Micro- 
biol., 8, 1953, 344.) 

con.cre.ti'vo.rus. L. noun concretum firm 
or solid matter; L. v. voro to devour or de- 
stroy; M.L. part. adj. co/ic?'e<iwrM.s concrete- 
destroying. 

Short, straight rods 0.5 by 1.5 to 2.0 
microns with square ends. Stain irregularly, 
showing deeply stained granules in poorly 
stained slender rods. Motile, presumably 
polar flagellate. Motility lost in older cul- 
tures. Single polar flagellum, two to three 
times the length of the organism (unpub- 
lished data). Gram-negative. 

Thiosulfate agar colonies: Minute, water- 
clear, whitish yellow on prolonged incuba- 
tion. No confluent growth. 

Thiosulfate liquid medium: Uniform tur- 
bidit\-, slight deposit of sulfur. No pellicle. 

Sulfur liquid medium: Uniform turbidity; 
floating sulfur granules fall to the bottom. 

Strictly aerobic. 

Temperature relations: Optimum, 28° C.; 
slow growth at 10° and 37° C.; death occurs 
at 55° C. 

Strictly autotrophic, utilizing atmos- 
pheric CO2 as the source of carbon; growth 
inhibited by higher concentrations of glu- 
cose, glycerol and lactate. Derives energy 
from its oxidation of elemental .sulfur, thio- 
sulfate and hydrogen sulfide, o.xidizing 
them ultimately to sulfate and sulfuric acid. 
Thiosulfate is oxidized with the intermedi- 
ate production of tetrathionate. 

Nitrogen sources: Utilizes ammonium- 
and nitrate-nitrogen equally well. Nitrate 
is not toxic whereas nitrite is. 

Optimum reaction: Growth occurs be- 
tween pH 6.0 and acid concentrations up to 
10 per cent. Sulfuric acid optimum is be- 
tween pH 2.0 and 4.0. 

Distinctive characters: Responsible for 
the rapid corrosion of concrete sewers and 
other concrete structures where the sewer 
air contains hydrogen sulfide. 

Habitat: Corroding concrete in sewers; 
also found in sewage and presumably in soil 
and fresh water. 

8. Thiobacillus thiooxidans Waksman 
and Joffe, 1922. (Jour. Bact., 7, 1922, 239.) 

thi.o.ox'i.dans. Gr. noun thiuvi sulfur; 
Gr. adj. oxys sharp, acid; M.L. v. oxido to 



make acid, to o.xidize; M.L. part. adj. thio- 
oxidans oxidizing sulfur. 

Short rods: 0.5 by 1.0 micron with rounded 
ends. Occur singly, in pairs or in chains. 
Motile by means of a single polar flagellum. 
Gram-negative (Starkey, Soil Sci., 39, 1935, 
210). 

Thiosulfate agar: Scant growth. Nearly 
transparent colonies. 

Sulfur broth: Uniform turbidity. No sedi- 
ment or surface growth. Medium becomes 
very acid (below pH 1.0). 

Thiosulfate broth: Uniform turbidity. 
Medium becomes acid, and sulfur is precipi- 
tated. 

Nitrogen sources: Utilizes ammonia- 
nitrogen but not nitrate-nitrogen, which is 
toxic. Asparagin, urea and peptone not 
utilized. 

Temperature relations: Optimum, be- 
tween 28° and 30° C. Slow growth at 18° 
and 37° C. Death occurs between 55° and 
60° C. 

Optimum reaction, between pH 2.0 and 
3.5. (Limiting reactions, pH 6.0 to less than 
pH 0.5.) 

Strictly autotrophic, deriving its energy 
from the oxidation of elemental sulfur and 
thiosulfate, o.xidizing these to sulfuric acid. 
It utilizes the CO 2 of the atmosphere as a 
source of carbon. 

Strictly aerobic. 

Distinctive characters: This species pro- 
duces more acid, from oxidation of sulfur, 
and continues to live in a more acid medium, 
than any other living organism yet reported, 
the hydrogen-ion concentration of the me- 
dium increasing to a pH 0.6 and less. 

Source: Isolated from composts of soil, 
sulfur and rock phosphate, and soils con- 
taining incompletel}' oxidized sulfur com- 
pounds. 

Habitat: Soil. 

9. Thiobacillus trautweinii Bergey et 
al., 1925. (Thionsaurebakterium, Trautwein, 
Cent. f. Bakt., II Abt., 53, 1921, 513; also 
see ibid., 61, 1924, 1; Bergey et al.. Manual, 
2nd ed., 1925, 39; Bacterium thiogenes 
Lehmann, in Lehmann and Neumann, 
Bakt. Diag., 7 Aufl., 2, 1927, 516.) 

traut.wein'i.i. M.L. gen. noun trautweinii 
of Trautwein; named for K. Trautwein, who 
first isolated and studied this species. 



ORDER I. PSEUDOMONADALES 



Short rods, 0.5 by 1.0 to 2.0 microns. Mo- 
tile by means of six to eight long flagella. 
Gram-negative. 

Gelatin stab: Slow liquefaction. No 
chromogenesis. 

Thiosulfate agar: Colonies small, white, 
1 mm in diameter. 

Thiosulfate liquid medium: Verj' little 
visible turbiditjs no sulfur precipitated. 
Produces sulfate and tetrathionate with in- 
crease in pH. Rate of thiosulfate oxidation 
increased by presence of organic com- 
pounds. 

No acid or gas from sugars. 

Nitrites and gas produced from nitrate- 
peptone broth; no ammonia produced. May 
live anaerobically in the presence of ni- 
trates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Starch is hydrolyzed. 

Lipolytic. 

Catalase-positive. 

Non-hemolytic. 

Temperature relations: Optimum, 27° C. 
Minimum, 6.9° C. Maximum, l^etween 36.5° 
and 40° C. Death occurs in 2 to 5 minutes at 
55° C. 



Optimum pH, between 7.9 and 8.5. pH 
limits, 6.0 and 10.0. 

Comments: Trautwein (Cent. f. Bakt., II 
Abt., 61, 1924, 5) regards his bacterium as 
being closely related to the fluorescent 
group and to the denitrifying bacteria of 
Burri and Stutzer. Starkey (Jour. Gen. 
Physiol., 18, 1935, 346) reports this species 
to be heterotrophic. However, Lehmann (in 
Lehmann and Neumann, Bakt. Diag., 7 
Aufl., ^, 1927, 516), under whom Trautwein 
did his work, reports that this species is a 
facultative autotroph as does Parker also 
(Jour. Gen. Microbiol., 3, 1953, 344). As 
facultatively autotrophic species are in- 
cluded in Thiobacillus as defined, this 
species has again been included in Thio- 
bacillus (see Manual, 2nd ed., 1925, 39). 
Starkey 's culture B and Parker's M cul- 
ures appear to be identical with Thioba- 
cillus trautweinii. 

Source: Isolated from soil and water 
(Trautwein) and from purified sewage from 
Wiirzburg (Lehmann). 

Habitat: Widely distributed in polluted 
waters and soil. 



FAMILY IV. PSEUDOMONADACEAE WINSLOW ET AL., 1917. 

(Winslow, Broadhurst, Buchanan, Krumwiede, Rogers and Smith, Jour. Bact., 2, 1917, 555.) 
Pseu.do.mo.na.da'ce.ae. M.L. fem.n. Pseudomonas tj'pe genus of the family; -aceae 
ending to denote a family; M.L. fern. pi. n. Pseudomonadaceae the Pseudomonas family. 

Cells elongate, straight rods, occasionally coccoid. Motile by means of polar flagella 
which are either single or in small or large tufts. A few species are non-motile. Gram-nega- 
tive. May possess either water-soluble pigments that diffuse through the medium or non- 
water-soluble pigments. Usually grow well and fairly rapidly on the surface of culture 
media. Aerobic. Frequently oxidative in their physiology but may be fermentative. Usually 
found in soil or water, including sea water or even heavy brines. Many plant and a few 
animal pathogens. 

Key to the genera of family Pseudomonadaceae. 

I. Attack glucose and other sugars either oxidatively or fermentatively. 

A. Genera in which the species are either known or are thought to attack glucose oxi- 
datively. 

1. Bacteria which do not produce readily detectable acetic acid though they may 
oxidize ethanol. May produce a water-soluble pigment which diffuses through 
the medium, 
a. Cultures may or maj' not produce a water-soluble pigment which is bluish, 
greenish or brownish in color. Rose, lilac- and yellow-colored, diffusible pig- 
ments occasionally occur. 



FAMILY IV. PSEUDOMONADACEAE »« 

Genus I. Pseudomonas, p. 89. 
aa. Cultures develop a yellow, non-water-soluble pigment. Cells normally mono- 
trichous. Mostlj^ plant pathogens which cause a necrosis. 

Genus II. Xanthomonas, p. 152. 
2. Bacteria which produce readily detectable amounts of acetic acid bj- the oxida- 
tion of ethanol. The vinegar bacteria. 

Genus III. Acetobacter, p. 183. 
B. Genera in which the species ferment glucose, usually with the production of H2 and 
CO2. 

1. Cells carry out a fermentation like that of the coliform bacteria. Usually produce 
acid and gas from glucose. 

a. Cells not known to fix free atmospheric nitrogen. 

b. Water organisms. Common species cause diseases of fishes. Also found in 
leeches. Not luminescent. 

Genus IV. Aeromo?ias, p. 189. 
bb. Luminescent bacteria commonly found on dead fishes and Crustacea on 
salt-water beaches. 

Genus V. Photobacterium , p. 193. 
aa. Cells fix free atmospheric nitrogen. 

Genus VI. Azotomonas, p. 198. 

2. Cells carry out an alcoholic fermentation similar to that of yeasts. 

Genus VII. Zymomonas, p. 199. 
II. Do not attack carbohydrates or, if so, produce only slight amounts of acid from glu- 
cose and similar sugars. Includes certain species which require at least 12 per cent salt 
for growth. 

A. Do not require salt in excess of 12 per cent for growth. 

1. Cells not embedded in a gelatinous matrix. 

a. Cells rod-shaped. 

b. Soil and water bacteria that are known to dissimilate alkylamines. 
Genus VIII. Protaminobacter , p. 200. 
bb. Soil and water bacteria that are known to dissimilate alginic acid. 
Genus IX. Alginovwnas , p. 202. 
aa. Soil bacteria that are known to utilize phenol and similar aromatic com- 
pounds. Cells may be branched. 

Genus X. Mycoplana, p. 204. 

2. Cells embedded in a gelatinous matrix; this matrix may be of a branching form. 

Genus XI. Zoogloea, p. 206. 

B. Requires at least 12 per cent salt before growth will take place. 

Genus XII. Halobacterium, p. 207. 

Genus I. Pseudomonas Migula, 1894* 

{Chlorobacterium Guillebeauf, Landw. Jahrb. d. Schweiz, 4, 1890, 32; Migula, 
Arb. bakt. Inst. Karlsruhe, 1, 1894, 237.) 

Pseu.do'mo.nas or Pseu.do.mo'nasJ. Gr. pseudes false; Gr. monas a unit, monad; M.L. 
fem.n. Pseudomonas false monad. 

Cells monotrichous, lophotrichous or non-motile. Gram-negative. Frequently develop 

* Completely revised by Dr. Wm. C. Haynes, Northern Utilization Research Branch, 
U.S.D.A., Peoria, Illinois (Species Nos. 1-58) and by Prof. Walter H. Burkholder, Cornell 
University, Ithaca, New York (Species Nos. 59-149), September, 1953. 

t See Footnote, p. 65. Also see Internat. Bull. Bact. Nomen. and Tax., 2, 1952, 121, foi 
a proposal to conserve Pseudomonas Migula. 

t The former accords with the Latin rules of accentuation; the latter is commonly used. 



90 ORDER I. PSEUDOMONADALES 

fluorescent, diffusible pigments of a greenish, bluish, violet, lilac, rose, yellow or other 
color. Sometimes the pigments are bright red or yellow and non-diffusible; there are many 
species that fail to develop any pigmentation. The majority of species oxidize glucose to 
gluconic acid, 2-ketogluconic acid or other intermediates. Usually inactive in the o.xidation 
of lactose. Nitrates are frequently reduced either to nitrites, ammonia or to free nitrogen. 
Some species split fat and/or attack hydrocarbons. Many species are found in soil and 
water, including sea water or even heavy brines. Many are plant pathogens; verj^ few are 
animal pathogens. 

The borderline between the straight rods found in Pseudomonas and the curved rods 
found in Vibrio is not sharp : occasionally curved rods ma.y occur in species that normally 
are composed of straight rods, this variation sometimes being dependent upon the medium 
used. Recently, however, Shewan, Hodgkiss and Liston (Nature, 173, 1954, 208) have de- 
scribed a method employing antibiotics and a vibriostatic agent whereby a sharper differen- 
tiation between pseudomonads and vibrios may possibly be effected. Future studies of this 
nature may show that some of the species in the genus Pseudomonas should be transferred 
to the genus Vibrio, and vice versa. 

The type species is Pseudomonas aeruginosa (Schroeter) Migula. 

Key to the species of genus Pseudomonas. 

I. Soil and water forms. A few species are pathogenic to warm- and cold-blooded verte- 
brates. 
A. Soil and fresh-water forms (a few are pathogenic). 

1. Produce diffusible pigments, usually of a yellow, green or blue color; may be 
fluorescent. (Soluble pigments are not formed in all media. Furthermore, the 
ability to produce such pigments may be lost. Therefore, failure to observe sol- 
uble-pigment formation does not preclude identity with species listed in this 
category.) 

a. Grow in gelatin. 

b. Gelatin liquefied. 

c. Polar flagellate. 

d. Grows readily at 42°C. on ordinary media, 
e. Milk becomes alkaline. 

1. Pseudomonas aeruginosa. 
ee. Milk acidified. 

2. Pseudomonas pseudomallei. 
dd. Grow poorly or not at all at 42° C. 

e. Grow readily at 37° C. 

f. Not known to attack cellulose. 

g. Milk becomes alkaline, indole not produced. 

3. Pseudomonas reptilivora. 
gg. Milk acidified, indole produced. 

4. Pseudomonas caviae. 

ggg. Action on milk and indole production unre- 
corded. 

5. Pseudomonas horeopolis. 
ff. Attack cellulose. 

g. Milk becomes alkaline, coagulated and pep- 
tonized, and litmus is reduced. 

6. Pseudomonas effusa. 
gg. No growth in milk. 

7. Pseudomonas ephemerocyanea. 



FAMILY IV. PSEUDOMOXADACEAE 91 

ee. Grow poorly or not at all at 37°C. 

f. Reaction in milk becomes acid or alkaline, 
g. Acid reaction produced in milk. 

8. Pseudotnonas fairmontensis . 
gg. Alkaline reaction produced in milk. 

h. Produces crj'stals of chlororaphine. 

9. Pseudomonas chlororaphis. 
hh. Chlororaphine not produced. 

i. Indole produced. 

10. Pseudomonas myxogenes. 

11. Pseudomonas schuylkilliensis. 
ii. Indole not produced. 

j. Produces an intense, diffusible, yel- 
low to orange pigment in cream or in 
cream layer of milk. 

12. Pseudomonas sijnxantha. 

jj . Fail to produce diffusible, yellow pig- 
ment in cream or in cream laj-er of 
milk, 
k. Nitrites produced from nitrates. 

13. Pseudomonas fluorescens. 

kk. Nitrites not produced from ni- 
trates. 

14. Pseudomonas pavonacea. 

15. Pseudomonas geniculata. 

16. Pseudomonas sepiica. 

ii. Reaction in milk unchanged. Becomes blue in asso- 
ciation with lactic-acid bacteria. 

17. Pseudomonas syncyanea. 
cc. Non-motile. 

d. Produces iodinin. 

18. Pseudomonas iodinum. 
dd. Iodinin not produced. 

e. Grows poorly or not at all at 37° C. 

13. Pseudotnonas fluorescens (non- 
motile variety), 
ee. Grows readilj' at 37° C. 

19. Pseudomonas smaraydina. 
bb. Gelatin not liquefied. 

c. Polar flagellate. 

d. Grow readily at 37° C. 

e. Reaction in milk unchanged. 

20. Pseudomonas puiida. 
ee. Alkaline reaction in milk. 

f. Litmus reduced. 

21. Pseudomonas striata, 
ii. Litmus not reduced. 

22. Pseudomonas oralis. 
dd. Grow poorly or not at all at 37° C. 

e. Reaction in milk acid. 

f. Musty odor produced in culture media. 

23. Pseudomonas taetrolens. 



92 ORDER I. PSEUDOMONADALES 

ff. Musty odor not produced in culture media. 

24. Pseudomonas incognita. 

25. Pseudomonas rugosa. 
ee. Reaction in milk alkaline. 

26. Pseudomonas mildenhergii. 

27. Pseudomonas convexa. 
cc. Non-motile. 

28. Pseudoinonas eisenbergii. 
aa. No growth in gelatin. 

29. Pseudomonas erythra. 
2. Soluble pigments not produced or not reported. 

a. Gelatin liquefied. 

b. Polar flagellate. 

c. Grow readil}" at 42° C. 

d. Alkaline reaction in milk. 

1. Pseudomonas aeruginosa (achro- 

mogenic variety' ). 
dd. Acid reaction in milk. 

2. Pseudomonas pseudomallei 

(achromogenic variety). 
cc. Grow readily at 25° C. but poorly or not at all at 37° C. 
d. Acid reaction in milk. 

e. May-apple odor produced in milk. Nitrites not produced 
from nitrates. 

30. Pseudomonas fragi. 

ee. Musty odor produced from all media. Nitrites and am- 
monia produced from nitrates. 

31. Pseudomonas perolens. 
dd. Alkaline reaction in milk. 

32. Pseudomonas mephitica. 

33. Pseudomonas putrefaciens . 

34. Pseudomonas cohaerens. 
aa. Gelatin not liquefied. 

b. Polar flagellate. 

c. Grow readily at 37° C. 

d. Action on cellulose not known or not reported, 
e. Acid produced in milk. 

35. Pseudomonas avMgua. 
ee. Milk imchanged. 

36. Pseudomonas oleovorans. 
eee. Action on milk unknown or unreported. 

f. Utilize hydrocarbons. 

37. Pseudomonas arvilla. 

38. Pseudomonas dacunhae. 

39. Pseudomonas desmolytica. 

40. Pseudomonas rathonis. 

41. Pseudomonas salopia. 
ff. Ability to utilize hydrocarbons unreported. 

g. Nitrites not produced from nitrates. 

42. Pseudomonas cruciviae. 

gg. Nitrates, nitrites, nitramids and NoO reduced 
to elemental nitrogen. 

43. Pseudomonas stutzeri. 



FAMILY IV. PSEUDOMONADACEAE 93 

dd. Attack cellulose 

e. Acid produced in milk. 

44. Pseudomonas tralncida. 
ee. Milk unchanged. 

45. Pseudomonas lasia. 
cc. Grow readily at 25° C. but poorly or not at all at 37°C. 

d. Action on cellulose unknown or unreported. 

e. Alkaline reaction in milk. Attacks riboflavin converting 
it to lumichrome. 

46. Pseudomonas riboflavina. 
ee. Reaction in milk unknown or unreported. 

f. Nitrates reduced to elemental nitrogen. 

47. Pseudomonas denitrificans . 

ff . Nitrates reduced to nitrites. Indole decomposed with 
formation of blue crj'stals of indigotin. 

48. Pseudomonas indoloxidans. 
dd. Attacks cellulose. 

49. Pseudomonas mira. 
B. Sea-water and brine forms (a few are pathogenic). 

1. Produces pigments which are soluble in culture media. Gelatin liquefied. 

50. Pseudomonas nigrifaciens. 

2. Pigments soluble in culture media not produced. 

a. Gelatin liquefied. 

b. Polar flagellate. 

c. No growth in milk. 

d. "Indole produced; nitrites produced from nitrates. 

51. Pseudomonas ichthyodermis. 
dd. Indole not produced; nitrites not produced from nitrates. 

e. Produces hydrogen sulfide and ammonia from tr5^ptone: 
no acid from glucose. 

52. Pseudomonas marinoglutinosa . 
ee. Hydrogen sulfide not produced; glucose acidified. 

53. Pseudomonas memhranoformis . 
cc. Action in milk unknown or unreported. 

d. Digests agar. 

54. Pseudomonas gelatica. 
dd. Do not digest agar. 

e. Deposit CaCOs in sea-water gelatin and in agar media in 
old cultures. Do not grow in 12 to 30 per cent salt solu- 
tions. 

55. Pseudomonas calcis. 

56. Pseudomonas calciprecipitans. 
ee. Does not deposit CaCOs in sea-water gelatin or in agar 

media. Grows well in 12 to 30 per cent salt solutions. 
56a. Pseudomonas halestorga. 
bb. Non-motile. Cellulose attacked. Insoluble yellow pigment produced. 

57. Pseudomonas iridescens (gela- 

tin-liquefying variety), 
aa. Gelatin not liquefied, 
b. Polar flagellate. 

c. Does not attack cellulose. Produces an insoluble purjjle pigment 
in vegetable extracts. 

58. Pseudomonas beijerinckii . 



94 ORDER I. PSEUDOMONADALES 

bb. Non-motile. 

c. Cellulose attacked. Produces an insoluble yellow pigment. 

57. Pseudomonas iridescens (non- 
gelatin-liquefying variety) . 
II. Plant pathogens, causing leaf spot, leaf stripe and similar diseases. (Also see Host Plant 
Key, p. 96.) 

A. Green fluorescent pigment produced. 
1. Gelatin liquefied. 

a. Acid from sucrose. 

b. Growth in 5 per cent salt. 

59. Pseudomonas aceris. 

60. Pseudomonas angulata. 

61. Pseudomonas aptata. 

62. Pseudomonas primulae. 

63. Pseudomonas viridilivida. 
bb. No growth in 5 per cent salt. 

c. Beef peptone agar turns deep brown. 

64. Pseudomonas delphinii. 
cc. Beef peptone agar imcolored. 

d. Colonies yellow. 

65. Pseudomonas cepacia. 
dd. Colonies white to cream. 

66. Pseudomonas apii. 

67. Pseudomonas asplenii. 

68. Pseudomonas berberidis. 

69. Pseudomonas coronafaciens . 

70. Pseudomonas lachrymans. 

71. Pseudomonas maculicola. 

72. Pseudomonas mangiferaeindicae. 

73. Pseudomonas marginata. 

74. Pseudomonas medicaginis. 

75. Pseudomonas phaseolicola . 

76. Pseudomonas pisi. 

77. Pseudomonas syringae. 

78. Pseudomonas tomato. 
bbb. Growth in salt solution not recorded. 

79. Pseudomonas atrofaciens. 

80. Pseudomonas cumini. 

81. Pseudomonas desaiana. 

82. Pseudomonas erodii. 

83. Pseudomonas lapsa. 

84. Pseudomonas martyniae. 

85. Pseudomonas matthiolae. 

86. Pseudomonas 7uorspru?iorum. 

87. Pseudomonas papulans. 

88. Pseudomonas pseudozoogloeae. 

89. Pseudomonas rimaefaciens . 

90. Pseudomonas striafaciens. 

91. Pseudomonas tabaci. 



aa. No acid from sucrose, 
b. Lipolytic. 



92. Pseudomonas polycolor 



FAMILY IV. PSEUDOMONADACEAE 



95 



bb. Not lipolytic, 
bbb. Lipolytic action not reported. 



93. Pseudomonas viridiflava. 



aaa. Acid from sucrose not i-eported. 



2. Gelatin not liquefied, 
a. Acid from sucrose. 



I. No acid from sucrc 
b. Non-motile. 



bb. Motile. 



aaa. Acid from sucrose not reported. 



94. Pseudomonas 

95. Pseudomonas 

96. Pseudomonas 

97. Pseudomonas 

98. Pseudomonas 

99. Pseudomonas 

100. Pseudomonas 

101. Pseudomonas 

102. Pseudomonas 

103. Pseudomonas 

104. Pseudomonas 

105. Pseudomonas 

106. Pseudomonas 

107. Pseudomonas 

108. Pseudomonas 



ananas, 
bowlesiae . 
ligustri. 
marginalis. 
sesami. 
setariae. 
tolaasii. 
washingtoniae . 

harkeri. 

be tie. 

gladioli. 

niellea. 

panacis. 

ribicola . 

xanthochlora. 



109. Pseudomonas aleuritidis. 

110. Pseudomonas glycinea. 

111. Pseudomonas savastanoi. 

112. Pseudomonas tonelliana. 



113. Pseudo?nonas cissicola. 

114. Pseudomonas calendulae. 

115. Pseudomonas dehor ii. 

116. Pseudomonas nectarophila. 

117. Pseudomonas viburni. 



B. Green fluorescent pigment 
1. Gelatin liquefied. 

a. Acid from sucrose, 
b. Beef -peptone 



118. Pseudomonas mori. 

119. Pseudomonas stizolobii. 

120. Pseudomonas viciae. 
not produced or not reported. 



agar turns dark brown. 

121. Pseudomonas alliicola. 

122. Pseudomonas gardeniae. 
bb. Beef-peptone agar uncolored or only slightly so. 

c. Colonies tan to brown. 

123. Pseudomonas caryophylli . 

124. Pseudomonas solanacearum. 
cc. Colonies white or colorless. 

125. Pseudomonas casianeae. 

126. Pseudomonas passiflorae. 

127. Pseudomonas seminum. 

128. Pseudomonas vitiswoodrowii. 



96 



ORDER I. PSEUDOMOXADALES 



aa. No acid from sucrose, 
aaa. Acid from sucrose not reported. 



2. Gelatin not liquefied, 
a. Acid from sucrose. 



aa. No acid from sucrose. 



aaa. Acid from sucrose not reported. 



3. Gelatin liquefaction not reported. 



129. Pseudomonas fabae. 



130. Pseudouionas 

131. Pseudomonas 

132. Pseudomonas 

133. Pseudomonas 

134. Pseudomonas 

135. Pseudomonas 

136. Pseudomonas 



astragali. 

colurnae. 

iridicola. 

levistici. 

viauhlancii. 

polygoni. 

radiciperda. 



137. Pseudomonas cattleyae. 

138. Pseudomonas dysoxyli. 

139. Pseudomonas helianthi. 

140. Pseudomonas melophthora. 

141. Pseudomonas alhoprecipitans . 

142. Pseudomonas andropogonis. 

143. Pseudomonas lignicola. 

144. Pseudomonas petasitis. 

145. Pseudomonas woodsii. 

146. Pseudomonas eriobotryae. 

147. Pseudomonas panicimiliacei . 

148. Pseudomonas salicivp.rda 

149. Pseudomonas wieringae. 



HOST PLANT KEY 

Where the host plant is known, the following key will be foimd useful. 
I. Cause of necrotic spots on mushrooms. 

100. Pseudomonas tolaasii. 
II. Cause of spots on ferns, Asplenium nidus. 

67. Pseudomonas asplenii. 
III. Cause of leaf blights and streaks on monocotyledonous plants. 

A. Attack members of the family Amaryllidaceae. 

121. Pseudomonas alliicola. 
65. Pseudomonas cepacia. 

B. Attacks members of the family Bromeliaceae. 

94. Pseudomonas ananas. 

C. Attack members of the family Gramineae. 

141. Pseudomonas alboprecipitans. 

142. Pseudomonas andropogonis. 
79. Pseudomonas atrofaciens. 
69. Pseudomonas coronafaciens . 
81. Pseudomonas desaiana. 

83. Pseudomonas lapsa. 
147. Pseudomonas panicimiliacei. 
99. Pseudomonas setariae. 
90. Pseudomonas striafaciens . 



FAMILY IV. PSEUDOMONADACEAE 97 

D. Attack members of the family Iridaceae. 

104. Pseudoinonas gladioli. 
132. Pseudomonas iridicola. 
73. Pseudomonas marginata. 

E. Attacks members of the family Musaceae. 

134. Pseudomonas matihlancii. 

F. Attacks members of the family Orchidaceae. 

137. Pseudomonas cattleyae. 

G. Attacks members of the family Palmaceae. 

101. Pseudomonas washingtoniae . 
IV. Cause of leaf, stem and fruit spots on dicotyledonous plants. 

A. Attacks members of the famih' Aceraceae. 

59. Pseudomonas aceris. 

B. Attacks members of the family Anacardiaceae. 

72. Pseudomonas mangiferaeindicae. 

C. Attacks members of the family Apocynaceae. 

112. Pseudomonas tonelliana. 

D. Attacks members of the family Araliaceae. 

106. Pseudomonas panacis. 

E. Attacks members of the family Berberidaceae . 

68. Pseudomonas berberidis. 

F. Attacks members of the family Betulaceae . 

131. Pseudomonas colurnae. 

G. Attacks members of the family Caprifoliaceae. 

117. Pseudomonas vihurni. 
H. Attack members of the family Caryophyllaceae. 

123. Pseudomonas caryophylli. 

145. Pseudomonas woodsii. 
I. Attacks members of the family Chenopodiaceae. 

149. Pseudomonas wieringae. 
J. Attack members of the family Compositae. 

114. Pseudoynonas calendulae. 

115. Pseudomonas cichorii. 
139. Pseudomonas helianthi. 

97. Pseudomonas marginalis. 
144. Pseudomonas petasitis. 

63. Pseudomonas viridilivida. 
K. Attack members of the family Cruciferae. 

71. Pseudomonas maculicola. 

85. Pseudomonas matthiolae. 
L. Attacks members of the family Cucurbitaceae. 

70. Pseudomonas lachrymans. 
M. Attacks members of the family Euphorbiaceae. 

109. Pseudomonas aleuritidis. 
N. Attacks members of the family Fagaceae. 

125. Pseudoinonas castaneae. 
O. Attacks members of the family Geraniaceae. 

82. Pseudomonas erodii. 
P. Attack members of the family Legmninosae. 

130. Pseudomonas astragali. 

129. Pseudomonas fabae. 

110. Pseudomonas glycinea. 



98 ORDER I. PSEUDOMOXADALES 

74. Pseudomonas medicaginis. 

75. Pseudomonas phaseolicola. 

76. Pseudomonas pisi. 

136. Pseudomonas radiciperda. 
127. Pseudomonas seminum. 
119. Pseudomonas stizolohii. 

110. Pseudomonas viciae. 

93. Pseudomonas viridiflava. 
Q. Attacks members of the family Martyniaceae. 

84. Pseudomonas martyniae. 
R. Attacks members of the family Meliaceae. 

138. Pseudomonas dysoxyli. 
S. Attacks members of the family Moraceae. 

118. Pseudomonas mori. 
T. Attack members of the family Oleaceae. 

96. Pseudomonas ligustri. 

111. Pseudomonas savastanoi. 
U. Attacks members of the famih' Passifloraceae. 

126. Pseudomonas passiflorae. 
V. Attacks members of the family Pedaliaceae. 

98. Pseudomonas sesami. 
W. Attacks members of the iamily Piperaceae. 

103. Pseudomonas belle. 
X. Attacks members of the family Polygonaceae. 

135. Pseudomonas polygoni. 
Y. Attacks members of the family Primulaceae. 

62. Pseudomonas primulae. 
Z. Attacks members of the famih^ Ranunculaceae. 

64. Pseudomonas delphinii. 
AA. Attack members of the family Rosaceae. 

102. Pseudomonas harkeri. 
146. Pseudomonas eriobotryae. 
140. Pseudomonas melophthora. 

86. Pseudomonas morsprunorum. 
116. Pseudomonas nectarophila. 

87. Pseudomonas papulans. 
BB. Attacks members of the family Rubiaceae. 

122. Pseudomonas gardeniae. 
CC. Attacks members of the famil}^ Salicaceae. 

148. Pseudomonas saliciperda. 
DD. Attacks members of the family Saxifragaceae. 

107. Pseudomonas ribicola. 
EE. Attack members of the family Solanaceae. 

60. Pseudomonas angulata. 
105. Pseudomonas mellea. 
92. Pseudanonas polycolor. 

88. Pseudomonas pseudozoogloeae. 
91. Pseudomonas tabaci. 

78. Pseudomonas tomato. 
FF. Attacks members of the family Ulmaceae. 

143. Pseudomonas lignicola. 
GG. Attack members of the family Umbelliferae. 

66. Pseudomonas apii. 



FAMILY IV. PSEUDOMONADACEAE 



99 



95. Pseudomonas bowlesiae. 

80. Pseudomonas cumini. 
133. Pseudomonas levistici. 
HH. Attacks members of the family Vitaceae. 

113. Pseudomonas cissicola. 
II. Attack members of numerous families. 

61. Pseudomonas aplata. 
124. Pseudomonas solanacearum. 

11 . Pseudomonas syringae. 
108. Pseudomonas xanthochlora. 



1. Pseudomonas aeruginosa (Schroe- 
ter, 1872) Migula, 1900. {Bacterium aerugi- 
nosum Schroeter, in Cohn, Beitrage z. 
Biologic, 1, Heft 2, 1872, 126; Bacillus pyo- 
cyaneus Gessard, Compt. rend. Acad. Sci., 
Paris, 94, 1882, 536; Pseudomonas pyocyanea 
Migula, in Engler and PrantI, Die natiirl. 
Pflanzenfam., 1, la, 1895, 29; Migula, Syst. 
d. Bakt., 2, 1900, 884.) 

ae.ru. gi.no'sa. L. adj. aeruginosus full of 
copper rust or verdigris, hence green. 

Common name: Blue pus organism. 

Rods, 0.5 to 0.6 b}' 1.5 microns, occurring 
singly, in pairs and short chains. Motile, 
possessing one to three polar flagella. 
(Monotrichous according to Reid, Naghski, 
Farrell and Haley, Penn. Agr. E.xp. Sta., 
Bull. 422, 1942, 6.) Gram-negative. 

Gelatin colonies: Yellowish or greenish 
yellow, fringed, irregular, skein-like, granu- 
lar, rapidly liquefying. 

Gelatin stab: Rapid liquefaction. The 
fluid assumes a yellowish green or bluish 
green color. 

Agar colonies: Large, spreading, grayish 
with dark center and tran.slucent edge, ir- 
regular. Medium greenish. 

Agar slant: Abundant, thin, white, glis- 
tening, the medium turning green to dark 
brown or black, fluorescent. 

Broth: Marked turbidity with thick pel- 
licle and heavy sediment. Medium yellowish 
green to blue, with fluorescence, later 
brownish. Often produces pyocyanine, fluo- 
rescein and pyrorubrin (Meader, Robinson 
and Leonard, Am. Jour. Hyg., 5, 1925, 682). 

Litmus milk: A soft coagulum is formed, 
with rapid peptonization and reduction of 
litmus. Reaction alkaline. 

Potato: Luxuriant, dirty brown, the me- 
dium becoming dark green. 



Indole usually not produced (Sandiford, 
Jour. Path, and Pact., U, 1937, 567). 

Nitrates reduced to nitrites and nitrogen. 

Glucose, fructose, galactose, arabinose, 
maltose, lactose, sucrose, dextrin, inulin, 
glycerol, mannitol and dulcitol are not fer- 
mented. Glucose oxidized to gluconic acid, 
2-ketogluconic acid and other intermediates 
(Lockwood, Tabenkin and Ward, Jour. 
Bact., 42, 1941, 51; Hajmes, Jour. Gen. 
Microbiol., 5, 1951,939). 

Blood serum: Liquefied. Yellow liquid, 
greenish on surface. 

Blood hemolyzed. 

Cultures have marked odor of trimethyl- 
amine. 

Aerobic, facultative. 

Optimum temperature, 37° C. Good 
growth at 42° C. 

Pathogenic for rabbits, guinea pigs, rats 
and mice. 

Distinctive characters: Some strains pro- 
duce p.yocyanine, a phenazine derivative 
which is extractable from alkaline media 
with chloroform as a deep blue pigment. 
Upon addition of acid, the color is trans- 
formed to red and becomes insoluble in 
chloroform. The ability to grow well at 
42° C, to oxidize gluconic acid to 2-keto- 
gluconic acid and to produce a slime in 
potassium gluconate media permits identifi- 
cation even though pyocyanine is not 
formed (Haynes, loc. cit.). 

Source: Pus from wounds. Regarded as 
identical with one of the plant pathogens 
(Pseudomonas polycolor) by Elrod and Braun 
(Jour. Bact., U, 1942, 633). 

Habitat: Cause of various human and 
animal lesions. Found in polluted water and 



100 



ORDER I. PSEUDOMONADALES 



2. Pseudoiiionas pseudomallei (Whit- 
more, 1913) Haynes, comb. nov. {Bacilhis 
pseudomallei Whitmore, Jour. Hyg., 13, 
1913, 1; Bacillus whitmori Stanton and 
Fletcher, Trans. 4th Cong. Far East Assn. 
Trop. Med., ^, 1921, 196; also see Jour. Hyg., 
23, 1925, 347; Malleomyces pseudomallei 
Breed, in Manual, 5th ed., 1939, 300; 
Loefflerella pseudomallei Brindle and Cowan, 
Jour. Path, and Bact., 63, 1951, 574.) 

pseu.do.mal'le.i. Or. adj. pseudes false; 
L. noun malleus the disease glanders; M.L. 
noun pseudomalleus false glanders; M.L. 
gen. noun pseudoviallei of false glanders. 

Short rods, with rounded ends, occurring 
singly and in short chains. Motile. Possess 
1 to 4 polar flagella (Brindle and Cowan, 
ibid., 571) ; this was confirmed by de Lajudie, 
Fournier and Chambon (Ann. Inst. Past., 
85, 1953, 112). Show bipolar staining. Gram- 
negative. 

Gelatin stab: Moderate, crateriform 
liquefaction. 

Agar colonies: Circular, slightly raised, 
thick, opaque, cream-colored with irregular 
margin. 

Glycerol agar slant: Wrinkled, thick, 
rugose, cream-colored growth. 
Broth: Turbid with pellicle. 
Litmus milk: Curdling with slowly de- 
veloped acidity; pink sediment; may be 
digested. 

Potato: Vigorous, cream-colored growth. 
Indole not produced. 

Acid from glucose, maltose, lactose, 
sucrose and mannitol. 

Grows in simple, chemically defined media 
containing single amino acids or the am- 
monium salt of certain organic acids as the 
sole carbon, nitrogen and energy source in a 
mineral salt base (Levine, Dowling, Even- 
son and Lien, Jour. Bact., 67, 1954, 350). 
Blood serum slowly liquefied. 
Aerobic, facultative. 

Optimum temperature, 37° C; but will 
grow readily at 42° C. (Cowan, personal 
communication, March, 1955). 

Distinctive character: Brygoo and Rich- 
ard (Ann. Inst. Past., 83, 1952, 822) report 
that a large number of strains, isolated in 
Saigon, produce a yellow pigment which is 
extractable in 2 per cent boiling HCl ; a few 
of these strains become non-pigmented 



when cultured on glycerol agar media. While 
this pigment has sometimes been described 
as water-soluble, Brindle and Cowan (op. 
cit., 1951, 574) suggest that this species may 
be more closely related to the species placed 
in Xanthomonas than to those placed in 
Pseudomonas. The xanthomonads develop 
yellow, non-diffusible, carotenoid pigments. 

Source: Isolated from lesions and blood in 
rats, guinea pigs, rabbits and man; also iso- 
lated once from a transient nasal discharge 
in a horse, once from a splenic abscess in a 
cow and once from a fatal case of an infected 
sheep. Virulent and avirulent strains can 
also be readily isolated from water at 
Saigon, Indochina, if appropriate media are 
used (Fournier and Chambon, personal 
communication, 1955). 

Habitat: Glanders-like infections (melioi- 
dosis) in rats, guinea pigs, rabbits and man 
in India, Federated Malay States and Indo- 
China. 

3. Pseudomonas reptilivora Caldwell 
and Ryerson, 1940. (Pseudomonas reptilivor- 
ous (sic) Caldwell and Ryerson, Jour. Bact., 
39, 1940, 335.) 

rep.ti.li'vo.ra. L. n. reptile a reptile; 
L. V. voro to devour; M.L. adj. reptilivorus 
reptile-destroying. 

Rods, 0.5 by 1.5 to 2.0 microns, occurring 
singly, in pairs and in short chains. Actively 
motile with two to six polar flagella. Gram- 
negative. 

Gelatin colonies: After 24 hours, small, 
circular, smooth, entire. Liquefaction. 
Medium becomes yellowish green fluores- 
cent. 

Gelatin stab: Infundibuliform liquefac- 
tion becoming stratiform. Putrid odor 
present. 

Serum slant: Liquefied. 

Agar cultures: Circular, smooth, glisten- 
ing, slightly raised, butyrous, translucent, 2 
mm in diameter. 

Agar slant: Growth abundant, smooth, 
filiform, glistening, butyrous and translu- 
cent. 

Broth: Turbid with pellicle and sediment. 
Putrid odor. 

Litmus milk: Alkaline, peptonization, 
complete reduction. Disagreeable odor. 

Potato: Growth moderate, spreading. 



FAMILY IV. PSEUDOMONADACEAE 



101 



i^listening, yellowish gray to creamy. Dis- 
agreeable odor. Medium becomes brownish 
gray. 

Indole not produced. 

Nitrites not produced from nitrates. 

Acetylmethjdcarbinol not produced. 

Hydrogen sulfide not produced. 

Slightly acid, becoming alkaline in glu- 
cose. No acid from arabinose, .xylose, lactose, 
sucrose, maltose, trehalose, raffinose, man- 
nitol, dulcitol, inositol or salicin. 

Starch not hydrolyzed. 

Pathogenic for guinea pigs and rabbits, 
horned lizards, Gila monsters and chuck- 
wallas. Marked hemolysis of rabbit cells 
and slight hemolysis of Gila monster cells 
suspended in agar. 

Temperature relations: Optimum, 20° to 
25° C. Maximum, 37° C. A retest of several 
strains of this organism by Haynes shows 
that it grows well at 37° C. and is closelj^ 
related to, though not identical with, 
Pseudomonas aervginosa Migula. 

Distinctive characters: Yellowish green 
fluorescence present only in meat infusion 
media. The pigment is water-soluble, but 
insoluble in chloroform. Pathogenic for 
guinea pigs, rabbits, horned lizards and 
chuckwallas. 

Source: Isolated from a bacterial disease 
of horned lizards and Gila monsters. 

Habitat: Pathogenic for lizards. 

4. Pseudomonas caviae Scherago, 1936. 
(Jour. Bact., 31, 1936, 83; also see Jour. Inf. 
Dis., 60, 1937, 245.) 

ca'vi.ae. M.L. fem.noun Cavia generic 
name of the guinea pig; from So. American 
Indian, "cabiai", a guinea pig; caviae of 
Cavia. 

Rods, 0.6 to 1.0 by 1.5 to 3.0 microns, oc- 
curring singly and in pairs; rounded ends. 
Motile by means of 1 to 3 polar flagella. 
Encapsulated. Gram-negative. 

Gelatin stab: Infundibuliform liquefac- 
tion. 

Agar colonies: Circular, convex, smooth, 
iridescent and translucent, finely granular, 
entire. 

Agar slant: Growth abundant, grayish 
white, butyrous, filiform, glistening, trans- 
lucent, markedly iridescent. Medium even- 



tually tinged greenish j'ellow, becoming 
brownish yellow. 

Broth: Cloudy, pellicle, abundant light 
yellow granular sediment, becoming brown. 
IVIedium becomes j^ellow. 

Litmus milk: Acidified, coagulated, pep- 
tonized, litmus partially reduced. 

Potato: Growth scant, filiform, glisten- 
ing, light yellow to light orange, becoming 
light brown. 

Hydrogen sulfide not produced. 

Indole produced. 

Nitrites produced from nitrates. 

Blood serum not liquefied. 

Blood not hemolyzed. 

Sodium formate decomposed. 

Catalase-negative. 

Methyl red positive; acetylmethylcar- 
binol not produced. 

Citrate broth: No growth. 

Methylene blue reduced. 

Acid but no gas from glucose, fructose, 
galactose, maltose, cellobiose, mannitol, 
lactose, arabinose, sucrose, trehalose, sor- 
bitol, mannose, dextrin, salicin, glycerol, 
aesculin, am3^gdalin and starch. No acid 
from xylose, dulcitol, rhamnose, inulin, 
adonitol, raffinose, erythritol or inositol. 

Aerobic, facultative. 

Optimum temperature, 37° C. Grows at 
25° C. 

Source: Isolated from guinea pigs dead 
from epizootic septicemia. 

Habitat : From infected guinea pigs so far 
as known. 

5. Pseudomonas boreopolis Gray and 
Thornton, 1928. (Cent. f. Bakt., II Abt., 73, 
1928, 92.) 

bo.re.o'po.lis. Gr. boreas north; Gr. polis 
a city; M.L. fern. gen. n. boreopolis of North 
City. 

Rods, 0.5 to 1.0 by 2.0 to 3.0 microns, oc- 
curring singly and in pairs. Motile with one 
to five polar flagella. Gram-negative. 

Gelatin colonies: Liquefied. 

Gelatin stab: Liquefied. Medium red- 
dened by some strains. 

Agar colonies: Circular or amoeboid, 
white to buff, flat to convex, smooth, 
glistening, translucent border. 

Agar slant: Filiform, whitish, raised, 
smooth, glistening, fluorescent. 



102 



ORDER I. PSEUDOMONADALES 



Broth: Turbid. 

Nitrates reduced to nitrites by some 
strains. 

Starch not hydrolyzed. 

Acid produced from glucose by most 
strains. 

Attacks naphthalene. 

Aerobic, facultative. 

Grows at 35° to 37° C. 

Source: Isolated from soil. 

Habitat: Soil. 

6. Pseudomonas efifusa Kellerman et al., 
1913. (Kellerman, McBeth, Scales and 
Smith, Cent. f. Bakt., II Abt., 39, 1913, 515; 
also see Soil Science, 1, 1916, 472.) 
ef.fu'sa. L. adj. effusus spread out. 
Rods 0.4 by 1.7 microns. Motile by means 
of one to three polar flagella. Gram-nega- 
tive. 

Gelatin stab: Liquefied. A non-liquefying 
variety is also found. 

Agar slant: Luxuriant, glistening, moist, 
creamy, spreading growth. Medium be- 
comes greenish fluorescent. 

Peptone starch agar slant : Abundant, flat, 
moist, rich creamy growth. Medium shows 
greenish fluorescence. 

Broth: Turbid; viscid sediment. Medium 
becomes greenish fluorescent. 

Litmus milk: Alkaline. Coagulation and 
digestion. Litmus reduced. A variety that 
acts more slowly on litmus milk is also 
found. 

Potato: Abundant, creamy, glistening, 
brownish flesh-colored growth. 

Indole not produced. 

Nitrites produced from nitrates. 

Ammonia is produced. 

No acid from glucose, starch, lactose, 
sucrose, maltose, glj'cerol or mannitol. 

Starch hydrolysis weak. 

Cellulose is attacked. 

Aerobic, facultative. 

Temperature relations: Optimum, 37° C. 
Survives 60° C, but not 70° C, for 15 min- 
utes. 

Source: Isolated from soils in Utah. 

Habitat: Soil. 

7. Pseudomonas ephemerocyanea Ful- 
ler and Norman, 1943. (Jour. Bact., 46, 
1943, 274.) 

e.phe.me.ro.cy.a'ne.a. Gr. adj. epheme- 



rus short-lived; Gr. adj. ajaneus blue; M.L. 
adj. ephemerocyaneus ephemeral blue. 

Rods, 0.3 to 0.4 by 2.2 to 2.8 microns, 
straight to slightly bent with rounded ends, 
arranged singlj-. Motile by means of 1 to 3 
polar flagella. Gram-negative. 
Gelatin stab: Liquefied. 
Starch agar colonies: Pinpoint colonies 
in three days, 1 to 2 mm in 5 days. White 
becoming tan, raised, glistening, smooth, 
entire. 

Water-insoluble de.xtrin colonies: Pin- 
point colonies show an enzymic zone, white, 
convex, entire. 

Starch agar slant: Heavy gelatinous, 
light brown becoming deeper brown. 
Litmus milk: No visible growth. 
Indole not produced. 
Nitrites produced from nitrates. 
Starch hydrolyzed. 

Attacks glucose, lactose, maltose, galac- 
tose, arabinose and xylose. Utilizes cellu- 
lose, cellulosan, water-soluble and water- 
insoluble cellulose dextrins and pectin. Slow 
utilization of gum arable and calcium glu- 
conate. 

In mineral nutrient media, filter paper 
strips are disintegrated at the air-liquid 
interface with the formation of a transitory 
violet or blue color which becomes light 
brown. 

Peptone, yeast extract, nitrate and am- ■ 
monia serve as nitrogen sources. 
Aerobic. 

Optimum temperature, 22° to 35° C. 
Distinctive characters: In media con- 
taining cellulose a transitory intense blue 
or violet color develops. In aerated cultures 
the entire medium becomes blue. The pig- 
ment appears to be water-soluble. After a 
few hours the color becomes light brown. 
Source: Isolated from soil. 
Habitat: Soil. 

8. Pseudomonas fairmontensis 

(Wright, 1895) Chester, 1901. (Bacillus Fair- 
montensis (sic) Wright, Memoirs Nat. Acad. 
Sci., 7, 1895, 458; Chester, Man. Determ. 
Bact., 1901, 311.) 

fair.mon.ten'sis. Fairmount Park (Phila- 
delphia) place name; M.L. adj. fairmonten- 
sis pertaining to Fairmount. 

Medium-sized rods, occurring singly, in 



FAMILY IV. PSEUDOMONADACEAE 



103 



pairs and in chains. Motile, possessing a 
single polar flagellum. Gram-negative. 

Gelatin colonies: Circular, white, trans- 
lucent. Dark centers with a greenish shim- 
mer, thinner edges and faint radial lines. 

Gelatin stab: Crateriform liquefaction. 

Agar slant: Grayish white, glistening. 
Agar becomes green. 

Broth: Turbid; delicate pellicle; white 
sediment. Becomes green. 

Litmus milk: Acid, coagulated; litmus 
reduced. 

Potato: Raised, granular, spreading, vis- 
cid. Becomes brownish. 

Indole produced. 

Action on nitrates unknown. 

Aerobic, facultative. 

Optimum temperature, 20° to 25° C. Fails 
to grow at 35° C. 

Source: From water from the Schuylkill 
River. 

Habitat: Water. 

9. Pseudomonas chlororaphis (Guig 
nard and Sauvageau, 1894) Bergey et al. 
1930. (Bacillus chlororaphis Guignard and 
Sauvageau, Compt. rend. Soc. Biol., Paris 
1, 10 ser., 1894, 841; Bergey et al.. Manual 
3rd ed., 1930, 166.) 

chlo.ro'ra.phis. Gr. chlorus green; Gr 
noun rhaphis a needle; M.L. fem.n. chloro 
r aphis a green needle. 

Description taken from Lasseur (Ann. de 
la Sci. Agron., Ser. 4,2« Annee, 2, 1913, 165) 
While Guignard and Sauvageau {op. cit. 
1894, 841) found .spores in this species 
Gessard, on reisolation, could find no spores 
(Ann. de la Sci. Agron., Ser. 3, 6^ Ann^e, 2 
1911, 374). The identification of the reiso 
lated culture was confirmed by Guignard 
The original description is brief and inade- 
quate and is probably based on a contami- 
nated culture. 

Rods, 0.8 b}' 1.5 microns, with rounded 
ends, occurring singly and in pairs. Motile 
with one to si.\ polar flagella. Gram-nega- 
tive. After continued cultivation some cells 
decolorize slowly. 

Gelatin colonies: Circular, viscid, trans- 
parent, glistening, lobate margin with 
fluorescent corona. Dissociates readilj^ 
(Lasseur and Dupai.x-Lasseur, Trav. Lab. 



Microbiol. Fac. Pharm. Nancy, Fasc. 9, 
1936, 35). 

Gelatin stab : Rapid liquefaction. Fluores- 
cent. Chlororaphine crystals may form. 

Broth: Turbid, greenish, fluorescent. 
Crystals of green chlororaphine may form. 
Broth becomes viscous. 

Litmus milk: Alkaline; coagulated. Be- 
comes viscous. Chlororaphine crystals may 
form in the central part of the culture. Odor 
of coumarin. 

Potato: Citron-yellow layer. Crystals of 
chlororaphine are formed. 

Nitrites produced from nitrates. 

Indole not produced. 

Pigment formation: Asparagine, potas- 
sium phosphate, glycerol, sulfate of mag- 
nesium and sulfate of iron are indispensable 
to the formation of crystals of chlorora- 
phine. Green crystals develop slowly and 
poorly in peptone solutions, best in syn- 
thetic media. 

Aerobic, facultative. 

Optimum temperature, between 25° and 
30° C. Cultures killed in ten minutes at 
63° C. 

Pathogenic for mice, guinea pigs, frogs, 
fresh-water fishes and crayfishes. An e.xo- 
toxin is formed. 

Distinctive character: Produces a beauti- 
ful emerald-green pigment which crystal- 
lizes in cultures as fine needles in bundles 
or as needles radiating from a center. The 
crystals form slowly and are not always 
present. Other species of pseudomonads, 
e.g. Pseudomonas iodinum, form crystals. 
As this power is readily lost, it raises the 
question whether other species of green, 
fluorescent pseudomonads may not form 
crystals under proper conditions. 

Source: Isolated from dead larvae of the 
cockchafer. Later reisolated bj^ various 
French bacteriologists from contami- 
nated water supplies. 

Habitat: Decomposing organic matter 
and fresh water so far as known. 

10. Pseudomonas myxogenes Fuhr- 
mann, 1907. (Cent. f. Bakt., II Abt., 17, 
1907, 356.) 

myx.o'ge.nes. Gr. myxa slime; Gr. gennao 
to produce, beget; M.L. adj. myxogenes 
slime-producing. 



104 



ORDER I. PSEUDOMONADALES 



Rods, 0.4 to 0.5 by 1.0 to 1.5 microns, oc- 
curring singly and in pairs. Motile, possess- 
ing a bundle of five to seven polar flagella. 
Gram-negative. 

Gelatin colonies: Smooth, soft, flat, 
spreading, brownish yellow, entire. Medium 
becomes yellowish green fluorescent. 

Gelatin stab: Growth along stab. Lique- 
faction with yellowish white sediment. 

Agar colonies: Circular, raised, smooth, 
amorphous, entire. 

Agar slant: Lemon-yellow, moist, mu- 
coid, gistening, becoming light green- 
fluorescent. 

Broth: Turbid, with slimy white sedi- 
ment. No pellicle. 

Litmus milk: Flocculent precipitation. 
Slow peptonization with yellow serum. 
Alkaline. 

Potato: Dirty yellow, moist, glistening, 
entire. 

Indole produced. 

Nitrates reduced to nitrites and am- 
monia. No gas formed. 

Acid from glucose. No acid from lactose 
or sucrose. 

Aerobic, facultative. 

Optimum temperature, 22° C. Scant 
growth at 35° C. 

Distinctive character: Grows in broth 
containing up to 6 per cent by volume of 
alcohol. 

Source: Isolated from beer. 

Habitat: Found in materials undergoing 
alcoholic fermentation, but probably also 
occurs elsewhere. 

11. Pseudomona.s schuylkilliensis 

Chester, 1901. (Bacillus fluorescens schuyl- 
killiensis Wright, Memoirs Natl. Acad. 
Sci., 7, 1895, 448; Chester, Man. Determ. 
Bact., 1901, 320.) 

schuyl.kil.li.en'sis. Schujdkill, name of a 
river; M.L. adj. schuylkilliensis of the 
Schuylkill. 

Short rods, with rounded ends, occurring 
singly, in pairs and in chains. Motile, posses- 
sing a polar flagellum. Gram-negative. 

Gelatin colonies: Grayish white, translu- 
cent. Medium becomes bluish green fluores- 
cent. 

Gelatin stab: Slow crateriform liquefac- 
tion, with blue-green fluorescence. 



Agar slant: Grayish, translucent growth. 
Medium shows greenish fluorescence. 

Broth: Turbid, with delicate pellicle and 
blue-green fluorescence. Stringy sediment. 

Litmus milk: Alkaline. Coagulated, with 
slow reduction of litmus; peptonized. 

Potato: Brownish, spreading, viscid, 
thick. 

Indole jjroduced (trace). 

Aerobic, facultative. 

Does not grow at 35° to 36° C. 

Source: Isolated from Schuylkill River 
water. 

Habitat: Water. 

12. Pseudomonas synxantha (Ehren- 
berg, 1840) Holland, 1920. (Vibrio synxan- 
thus Ehrenberg, Verhandl. d. Berl. Akad., 
1840, 202; Holland, Jour. Bact., 5, 1920, 220.) 

syn.xan'tha. Gr. pref. syn- along with, 
together; Gr. adj. xanthus yellow; M.L. 
adj . synxanihus with yellow. 

Description from Hammer (Res. Bull. 20, 
Iowa Agr. Exp. Sta., 1915); also see Zim- 
mermann (Bakt. unserer Trink- und Nutz- 
wasser, Chemnitz, 2, 1890, 44). 

Rods, 0.5 to 0.6 by 1.3 to 2.2 microns, oc- 
curring singly and in pairs. Motile with 
polar flagella (Hammer, personal communi- 
cation, 1944). Gram-negative. 

Gelatin stab: Liquefied; a greenish tinge, 
a heavy, flocculent sediment and a partial 
membrane and ring appear in two weeks. 

Agar colonies: After 72 hours, large, 
spreading, transparent; bluish cast by re- 
flected light. Colonies may show flesh 
color (Zimmermann). 

Agar slant: Growth raised, shiny, white, 
becoming brown and heavy. 

Agar stab : Growth heaviest near the sur- 
face, becoming light brown, heavy, spread- 
ing. 

Broth: Turbid, becoming alkaline and 
green; pellicle and brittle membrane form 
in older cultures. With the addition of glu- 
cose or galactose, black granules form on 
the membranes of older cultures. 

Uschinsky's and Dunham's solutions: 
Turbid, occasionally becoming green. 

Litmus milk: Coagulated; casein digested 
in older cultures. Litmus reduced. 

Potato: Growth spreading, brown with 
greenish edges. 



FAMILY IV. PSEUDOMONADACEAE 



105 



Indole not produced. 

Acid but no gas from glucose, fructose, 
galactose and glycerol. No acid or gas from 
salicin or raffinose. 

Aerobic. 

Grows well at 20° C. 

Distinctive character: Produces an in- 
tense, diffusible, yellow to orange color in 
cream or in the cream layer of milk. 

Source: Isolated from bitter milk. 

Habitat: Milk and cream so far as is 
known. 

13. Pseudoinonas fluorescens INIigula, 
1895. (Bacilhis fluorescens liquefadens 
Fliigge, Die Mikroorganismen, 1886, 289; 
Migula, in Engler and Prantl, Die natiirl. 
Pflanzenfamilien, 1, la, 1895, 29.) 

flu.o.res'cens. L. fluor a flux; M.L. 
fluoresco to fluoresce; fluor-spar, a fluxing 
mineral which is fluorescent; M.L. part. 
ad] . fluorescens fluorescing. 

Rods, 0.3 to 0.5 by 1.0 to 1.8 microns, oc- 
curring singly and in pairs. Motile, posses- 
sing a polar flagellum; occasionally non- 
motile. Gram-negative. 

Gelatin colonies: Circular, with greenish 
center, lobular, liquefying quickly; occa- 
sionally viscid. 

Gelatin stab: Infundibuliform liquefac- 
tion, with whitish to reddish gray sediment. 

Agar slant: Abundant, reddish layer, be- 
coming reddish gray. The medium shows 
greenish to olive-brown coloration. 

Broth: Turbid, flocculent, with yellowish 
green pellicle and graj'ish sediment. 

Litmus milk: No coagulation; becoming 
alkaline. 

Potato: Thick, grayish yellow, spreading, 
becoming light sepia-brown in color; occa- 
sionally viscid. 

Indole not produced. 

Nitrates reduced to nitrites and am- 
monia. 

Acid from glucose. 

Blood serum liquefied. 

Aerobic. 

Optimum temperature, between 20° and 
25° C. 

Not pathogenic. 

Source: Water, sewage, feces. 

Habitat: Soil, water and occasionally 



foodstuffs that have become contaminated 
from these sources. 

14. Pseudomonas pavonacea Levine 
and Soppeland, 1926. (Bull. No. 77, Iowa 
State Agr. College, 1926, 41.) 

pa.vo.na'ce.a. L. adj. pavonaceus like a 
peacock's tail, variegated. 

Rods, 0.5 by 4.5 microns, with truncate 
ends, occurring singly and in chains. Old 
cell'- develop 2 to 4 knob-like processes. 
Sluggishly motile. Gram-negative. 

Gelatin stab: Crateriform liquefaction. 
Medium becoming brown. 

Agar colonies: Circular, raised, becoming 
green, amorphous, entire. 

Agar slant: Green, smooth, glistening, 
viscid, medium becoming dark brown. 

Broth: Turbid, with viscid sediment. Me- 
dium turned brown. 

Litmus milk: Slightly alkaline. Litmus 
reduced. Peptonized after 10 days. 

Potato: No growth. 

Hydrogen sulfide produced. 

Indole not produced. 

Neither nitrites nor gas produced from 
nitrates. 

Blood serum liquefied in 5 days. 

No acid or gas from glucose, lactose, 
sucrose or glycerol. 

Aerobic, facultative. 

Optimum temperature, 22° C. Scant 
growth at 37° C. 

Distinctive characters: Growth on solid 
media distinctly green. Not fluorescent. 
Medium becomes brown. 

Source: Isolated from activated sludge. 

15. Pseudomonas geniculata (Wright, 
1895) Chester, 1901. (Bacillus geniculatus 
Wright, Memoirs Nat. Acad. Sci., 7, 1895, 
459; Chester, Man. Determ. Bact., 1901, 
313.) 

ge.ni.cu.la'ta. L. adj. geniculatus jointed. 

Medium-sized rods, occurring singly, in 
pairs and in chains. Motile, possessing 1 to 
4 polar flagella. Gram-negative. 

Gelatin colonies: Circular, whitish, as- 
sume a greenish shimmer, translucent. Deep 
colonies yellowish. 

Gelatin stab: Infundibuliform liquefac 
tion. Sediment light pink. 



106 



ORDER I. PSEUDOMONADALES 



Agar slant: Grayish, glistening, translu- 
cent, limited. Agar becomes brownish green. 

Broth: Turbid, with slight gray pellicle 
and sediment. Broth becomes green. 

Litmus milk: Alkaline; reduction of lit- 
mus; slight coagulation. Serum becomes 
green. 

Potato: Thin, brownish, moist, glistening, 
viscid. 

Indole not produced. 

Aerobic, facultative. 

Optimum temperature, between 20° and 
25° C. No growth at 35° C. 

Source: From water from the Schuylkill 
River. 

Habitat: Water. 

16. Pseudomonas septica Bergey et al., 
1930. (Bacilhis fluorescens septicus Stutzer 
and Wsorow, Cent. f. Bakt., II Abt., 71, 
1927, 113; Bergey et al., Manual, 3rd ed., 
1930, 169.) 

sep'ti.ca. Gr. adj. septicus putrefactive, 
septic. 

Rods, 0.6 to 0.8 by 0.8 to 2.0 microns, oc- 
curring singly. Motile with a polar flagel- 
lum. Gram-negative. 

Gelatin stab: Infundibuliform liquefac- 
tion. 

Agar colonies: Circular with opalescent 
center and transparent periphery. 

Agar slant: Moderate, undulate margin. 

Broth: Turbid with fragile pellicle, green- 
ish in upper portion. 

Litmus milk: Alkaline, coagulated. 

Blood serum not liquefied. 

Acid from glucose. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Source: Isolated from diseased caterpil- 
lars. 

Habitat: From infected caterpillars so 
far as known. 

17. Pseudomonas syncyanea (Ehren- 
berg, 1840). Migula, 1895. (Vibrio syncyaneus 
Ehrenberg, Berichte ii.d. Verh. d. k. Preuss. 
Akad. d. Wissensch. z. Berlin, 5, 1840, 202; 
Migula, in Engler and Prantl, Die natiirl. 
Pflanzenfam., 1, la, 1895, 29.) 

syn.cy.a'ne.a. Gr. srjn- along w^ith, en- 
tirely; Gr. cyaneus dark blue, dark; M.L. 
adj. syncyaneus entirely blue. 



Rods with rounded ends, occurring singly, 
occasionally in chains, 0.7 by 2.0 to 4.0 
microns. Motile with two to four polar fla- 
gella. Gram-negative. 

Gelatin colonies: Flat, bluish, translu- 
cent. 

Gelatin stab: Surface growth shiny, 
grayish blue. The medium is colored steel- 
blue with greenish fluorescence. Gelatin is 
liquefied. Some strains do not liquefy. 

Agar slant: Grayish white streak. The 
medium takes on a bluish gray color with 
slight fluorescence. 

Broth: Turbid with marked fluorescence. 

Litmus milk: Unchanged. In association 
with lactic-acid bacteria the milk takes on a 
deep blue color. 

Potato: Yellowish gray, shiny layer, be- 
coming bluish gray. The tissue becomes 
bluish gray. 

Indole not produced. 

Nitrites not produced from nitrates. 

Aerobic, facultative. 

Optimum temperature, 25° C. 

Source: From milk that was bluish in 
color. 

Habitat: The cause of blue milk. 

18. Pseudomonas iodinum (Davis, 
1939) Tobie, 1939. (Chromobacierium io- 
dinum Davis, Zent. f. Bakt., II Abt., 100, 
1939, 273; Tobie, Bull. Assoc. Diplomes 
Microbiol. Fac, Nancy, No. 18, 1939, 16.) 

i.o.di'num. M.L. neut.noun iodinum 
iodine. 

Rods, 0.5 by 1.0 to 2.0 microns, occurring 
singly. Non-motile. Gram-negative. 

Gelatin stab: Stratiform liquefaction. 
Crystals of iodinin form. 

Agar colonies: Round, smooth, gray- 
white, moist, glistening. Dark purple crys- 
tals having the appearance of iodine crystals 
form in the growth and in the adjacent 
medium. This pigment is actually a phena- 
zine di-N-oxide, there being no iodine 
present (Clemo and Mcllwain, Jour. Chem. 
Soc, Pt. 1, 1938, 479; Clemo and Daglish, 
Jour. Chem. Soc, Pt. 1, 1950, 1481). 

Broth: Turbid. Crystals of iodinin form 
on bottom of tube. 

Litmus milk: Alkaline; slow reduction of 
litmus. 



FAMILY IV. PSEUDOMONADACEAE 



107 



Potato: Viscous, creamy, spreading, be- 
coming dark. 

Catalase-positive. 

Indole not produced. 

Nitrites produced from nitrates. 

No acid from carbohj-drates. 

Acetylmethylcarbinol not produced. 

Aerobic. 

Optimum temperature, 28° C. Grows at 
37° C. 

Distinguishing character: The pigment, 
iodinin, is readih' formed in any medium 
containing soluble nitrogenous compounds. 
Potassium and sodium citrates markedly 
stimulate pigment production. Yeast ex- 
tract is inhibitory to formation of iodinin, 
which is soluble in benzene, toluene, xylene, 
chloroform, carbon disulfide and ethyl ace- 
tate. Such solutions are ruby red. The pig- 
ment, like pyocyanin and chlororaphine, is a 
phenazine derivative. 

Source: Isolated from milk. 

Habitat: Unknown. 

19. Pseudomonas smaragdina (Mez, 

1898) Migula, 1900. {Bacillus smaragdinus 
foetidus Reiman, Inaug. Dissertation, 
Wiirzburg, 1887; Bacterium smaragdinum 
Mez, Mikroskopische Wasseranalyse, Ber- 
lin, 1898, 49; Migula, Svst. d. Bakt., £, 1900, 
890.) 

sma.rag'di.na. Gr. adj. smaragdinus of 
smaragdus, emerald -green. 

Small rods, occurring singly. Non -motile. 
Gram-negative. 

Gelatin colonies: Small, convex, irregular, 
whitish with greenish shimmer. 

Gelatin stab: Slight surface growth. In- 
fundibuliform liquefaction. The liquefied 
medium becomes light emerald-green in 
color. 

Agar colonies: Small, brownish yellow, 
convex. 

Agar slant: Abundant growth with green- 
ish fluorescence. 

Broth: Turbid. 

Litmus milk: Not coagulated. 

Potato: Dark brown, becoming chocolate- 
brown. 

Indole not produced. 

Nitrates not reduced. 

The cultures give off an odor resembling 
jasmine. 



Aerobic, facultative. 

Optimum temperature, 37° C. 

Subcutaneous and intravenous inocula- 
tions into rabbits cause death in 36 to 48 
hours. 

Source: Isolated from nasal secretions in 
ozena. 

Habitat: Unknown. 

20. Pseudomonas putida (Trevisan, 
1889) Migula, 1895. {Bacillus fluorescens 
putidus Fliigge, Die Mikroorganismen, 2 
Aufl., 1886, 288; Bacillus putidus Trevisan, 
I gen. e le specie d. Batteriacee, 1889, 18; 
Migula, in Engler and Prantl, Die natiir. 
Pflanzenfam., 1, la, 1895, 29.) 

])u'ti.da. L. adj. putidus stinking, fetid. 

Rods with rounded ends. Motile, posses- 
sing polar flagella. Gram-negative. 

Gelatin colonies: Small, finely granular, 
fluorescent with dark center, surrounded by 
a yellow zone, with pale gray margin. 

Gelatin stab: Dirty white surface growth, 
becoming greenish, fluorescent. No liquefac- 
tion. 

Agar colonies: Circular, raised, smooth, 
amorphous, entire, with fluorescent zone 
around the periphery. 

Agar slant: Yellowish green layer, be- 
coming fluorescent. 

Broth: Turbid, fluorescent. 

Litmus milk: Unchanged. 

Potato: Thin, gray to brownish, slim}- 
layer. 

Cultures give off odor of trimethylamine. 

Indole not produced. 

Nitrites produced from nitrates. 

Aerobic, facultative. 

Temperature relations: Optimum, 25° C. 
Will grow at 37° C. (Reid et al., Penn. Agr. 
Exp. Sta., Bull. 422, 1942,9). 

Relationship to other species: Identical 
with Pseudomonas flxiorescens Migula ac- 
cording to Lehmann and Neumann (Bact. 
Diag., 1, Aufl., 2, 1896, 271) except that it 
does not liquefy gelatin. See Pseudomonas 
eisenbergii Migula. 

Source: Isolated from putrid materials. 

Habitat: Putrefying materials; water. 

21. Pseudomonas striata Chester, 1901. 
{Bacillus striatus viridis Ravenel, Memoirs 



108 



ORDER I. PSEUDOMONADALES 



Nat. Acad. Sci., 8, 1896, 22; Chester, Man. 
Determ. Bact., 1901, 325.) 

stri.a'ta. L. v. strio to groove; L. part. adj. 
striatus grooved. 

Slender rods, of variable lengths, staining 
irregularl}^ occurring singly and in pairs. 
Motile, possessing polar flagella. Gram-nega- 
tive. 

Gelatin colonies: Circular, yellowish, with 
filamentous border. 

Gelatin stab: No liquefaction. 

Agar slant: Smooth, glistening, irregular, 
spreading. Agar becomes j-ellowish green. 

Broth: Turbid, becoming slightly greenish. 

Litmus milk: No coagulation; becoming 
alkaline; litmus reduced. 

Potato: Moist, glistening, spreading, be- 
coming chocolate-brown. 

Indole not produced. 

Aerobic. 

Grows well at 25° and 36° C. 

Source: Isolated from soil. 

Habitat: Soil. 

22. Pseudomonas ovalis Chester, 1901. 
(Bacillus fltmrescens ovalis Ravenel, Mem- 
oirs Nat. Acad. Sci., 8, 1896, 9; Chester, 
Man. Determ. Bact., 1901, 325.) 

o.va'lis. L. n. ovum an egg; M.L. adj. 
ovalis oval. 

Rods, short with rounded ends, occurring 
singly. Motile, possessing polar flagella. 
Gram-negative. 

Gelatin colonies: Irregular, lobate, 
slightly granular, translucent, grayish be- 
coming bluish. 

Gelatin stab: No liquefaction. Faintly 
green near surface. 

Agar colonies: Circular, opaque, entire, 
greenish fluorescence. 

Agar slant: Thin, spreading, greenish 
white. Agar becomes j'ellowish. 

Broth: Turbid, with pellicle and white 
sediment; faintly green. 

Potato: Scant, yellowish brown growth. 

Indole not produced. 

Aerobic, facultative. 

Grows well at 25° and 36° C. 

Source: Isolated from soil. 

Habitat: Soil. 



and Anderson, Jour. Bact., 23, 1932, 343; 
not Pseudomonas graveolens Migula, Syst. d. 
Bakt., 2, 1900, 934.) 

taet'ro.lens. L. adj. taeter offensive; L. 
part, olens having an odor; M.L. part. adj. 
taetrolens foul-smelling. 

Short rods with rounded ends, occurring 
singly, in pairs and in short chains. Motile 
(Levine and Anderson). One to five polar 
flagella (found on retest of cultures bj- 
Haynes, 1953). Gram-negative. 

Gelatin stab: Not liquefied. 

Agar colonies: Circular, slightly raised, 
smooth, entire, amorphous internal struc- 
ture. 

Agar slant: Growth abundant and tan- 
colored; medium darkened. Penetrating 
odor of must. 

Broth: Turbid; thin, oily pellicle and 
sediment. Odor of must. 

Litmus milk: Acid, coagulated; litmus 
reduced. 

Indole not produced. 

Nitrites not produced from nitrates. 

Hj'drogen sulfide produced. 

Starch not hydrolyzed. 

Acid but no gas produced from glucose, 
lactose, galactose, mannose, fructose, 
rhamnose and xjdose. Slight acidity in 
glycerol and mannitol. No acid or gas from 
aesculin, amygdalin, arabitol, dextrin, dul- 
citol, glycogen, inulin, maltose, melizitose, 
pectin, raffinose, salicin, sorbitol, starch, 
sucrose, xylan, arabinose, erythritol or 
trehalose. 

Aerobic. 

Catalase-positive. 

Optimum temperature, between 23° and 
25° C. Scant growth at 33° and 10° C. 

Distinctive character: A strong musty- 
odor develops in media in which this or- 
ganism grows. In this respect it resembles 
P. perolens which, however, liquefies gelatin 
and reduces nitrates. 

Source: Isolated from musty eggs; also 
from milk by Olsen and Hammer (Iowa 
State College Jour. Sci., 9, 1934, 125). 

Habitat : Found in various foods that have 
a musty odor; presumably widely dis- 
tributed. 



23. Pseudomonas laelrolens Haynes, 
7iom. nov. (Pseudomonas graveolens Levine 



24. Pseudomonas incognita Chester, 
1901. (Bacillus fluorescensincognitus'WTight, 



FAMILY IV. PSEUDOMONADACEAE 



109 



Memoirs Nat. Acad. Sci., 7, 1895, 436; 
Chester, Man. Determ. Bact., 1901, 323.) 

in.cog'ni.ta. L. adj. incognitus not ex- 
amined, unknown. 

Short rods, with rounded ends, occurring 
singly, in pairs and in chains. Motile, pos- 
sessing a polar flagellum. Gram-negative. 

Gelatin colonies: Thin, translucent, 
slightly granular, becoming greenish. Mar- 
gin undulate. The medium assumes a blue- 
green fluorescence. 

Gelatin stab: No liquefaction. 

Agar slant: Thin, moist, translucent. Agar 
becomes greenish. 

Broth: Turbid, becoming greenish. Pel- 
licle and whitish sediment form. 

Litmus milk: Slightly acid in a month. 
Litmus slowly reduced. 

Potato: Moist, glistening, spreading, 
brown. 

Indole is produced (trace). 

Aerobic, facultative. 

No growth at 35° to 36° C. 

Comment: Wright (op. cit., 1895, 441) 
described an organism that is very similar 
to this species except that it may produce a 
faint brownish green coloration in a gelatin 
stab; Wright named the organism Bacillus 
nexibilis {Bacterium nexibilis Chester, Ann. 
Rept. Del. Col. Agr. Exp. Sta., 9, 1897, 74; 
Pseudomonas nexibilis Chester, op. cit., 
1901, 309). 

Source: Isolated from water from the 
Schujdkill River. 

Habitat: Water. 

25. Pseudomonas rugosa (Wright, 1895) 
Chester, 1901. {Bacillus rugosus Wright, 
Memoirs Nat. Acad. Sci., 7, 1895, 438; 
Chester, Man. Determ. Bact., 1901, 323.) 

ru.go'sa. L. adj. rugosus full of wrinkles. 

Small rods, with rounded ends, occurring 
singl}^ in pairs and in chains. Motile, pos- 
sessing 1 to 4 polar flagella. Gram-negative. 

Gelatin colonies: Grayish, translucent, 
slightly raised, irregular, sinuous, radiately 
arose to entire. 

Gelatin stab : Dense grayish green, lim- 
ited, wrinkled, reticulate surface growth. 
No liquefaction. Medium becomes green. 

Agar slant: Grayish white, limited, 
slightl}^ wrinkled, translucent. Agar be- 
comes green. 



Broth: Turbid, with thin whitish pellicle 
and sediment. 

Litmus milk: Acid, coagulated, partly re- 
duced. 

Potato: Moist, glistening, brown, spread- 
ing. 

Indole is produced (trace). 

Aerobic. 

Optimum temperature, 30° C. Does not 
grow at 35° C. 

Source: From water from the Schuylkill 
River. 

Habitat: Water. 

26. Pseudomonas mildenbergii Bergey 
et al., 1930. (Der Blaubacillus, Mildenberg, 
Cent. f. Bakt., II Abt., 56, 1922, 309; Bergey 
et al., Manual, 3rd ed., 1930, 172.) 

mil.den.ber'gi.i. Mildenberg, a patro- 
nymic; M.L. gen. noun mildenbergii of Mil- 
denberg. 

Rods, 0.3 to 0.5 by 1.0 to 3.5 microns, 
with rounded ends, occurring singly. Mo- 
tile, possessing polar flagella. Gram-nega- 
tive. 

Gelatin colonies: Circular, lobed, smooth, 
glistening, slightly raised, steel-blue, entire. 

Gelatin stab: No liquefaction. 

Agar colonies: Small, circular, yellowish 
or reddish yellow, entire, becoming lobed, 
grayish green, iridescent. The medium be- 
comes dirty grayish green. 

Agar slant: Smooth, spreading, slimy, 
glistening, grayish green to dark green, 
fluorescent. 

Broth: Turbid green, iridescent to opales- 
cent with slimy sediment. 

Litmus milk: Not coagulated, blue ring. 

Potato: Slimj^, glistening, spreading, steel 
blue. 

Indole not produced. 

Nitrites not produced from nitrates. 

Aerobic, facultative. 

Optimum temperature, 25° C. 

Source : Isolated from air. 

27. Pseudomonas eonvexa Chester, 
1901. {Bacillus fluorescens convexus Wright, 
Memoirs Nat. Acad. Sci., 7, 1895, 438; 
Chester, Man. Determ. Bact., 1901, 325.) 

con.vex'a. L. adj. convexus vaulted, con- 
vex. 

Short, thick rods, with rounded ends. 



no 



PSEUDOMONADALES 



Motile, possessing a polar flagellum. Gram- 
negative. 

Gelatin colonies: Circular, convex, glis- 
tening, greenish, translucent. The medium 
becomes blue-green, fluorescent. 

Gelatin stab: Light green, raised, glisten- 
ing surface growth. No liquefaction. Me- 
dium becomes blue-green fluorescent. 

Agar slant: Moist, translucent, glisten- 
ing, light greenish. The medium assumes a 
greenish color. 

Broth: Turbid, becoming greenish. 

Litmus milk: No coagulation; alkaline. 

Potato: Pale brown, spreading. 

Indole not produced. 

Aerobic, facultative. 

Little or no growth at 35° to 36° C. 

Source: From water from the Schuylkill 
River. 

Habitat: Water. 

28. Pseudomonas eisenbergii Migula, 
1900. (Fluorescirender Bacillus No. 18, 
Eisenberg, Bakt. Diag., 1 Aufl., 1886, Taf. 
7; Bacillus fluorescens non liquefaciens Eis- 
enberg, Bakt. Diag., 3 Aufl., 1891, 145; Mig- 
ula, Syst. d. Bakt., 3, 1900, 913; Pseud- 
omonas non-liquefaciens Bergey et al.. 
Manual, 1st ed., 1923, 132.) 

eis.en.ber'gi.i. Named for James Eisen- 
berg, the bacteriologist who first described 
this species; M.L. gen.n. eisenbergii of 
Eisenberg. 

Short, slender rods with rounded ends. 
Non-motile. Gram-negative. 

Gelatin colonies: Fern-like surface col- 
onies. Medium around colonies has a pearly 
luster. 

Gelatin stab: Surface growth has fluores- 
cent shimmer. Scant growth along stab. No 
liquefaction. 

Agar slant: Greenish growth. 

Broth: Turbid, fluorescent. 

Litmus milk: Unchanged. 

Potato: Diffuse, brownish laj-er. The sur- 
face acquires a grayish blue color. 

Indole not produced. 

Nitrites produced from nitrates. 

Acid from glucose. 

Blood serum liquefied. 

Aerobic. 

Optimum temperature, 25° C. 



Not pathogenic. 
Habitat : Water. 

29. Pseudomonas erythra Fuller and 
Norman, 1943. (Jour. Bact., 46, 1943, 276.) 

e'ry.thra. Gr. adj. erythrus red. 

Rods, 0.2 to 0.4 by 1.2 to 1.5 microns, with 
rounded ends, usually arranged singly. 
Motile with a single polar flagellum. Encap- 
sulated. Gram-negative. 

Gelatin stab: No growth. 

Starch agar: No growth. 

Water-insoluble dextrin agar: Scant 
growth. Subsurface colonies appear after 
8 to 10 days. Colonies are angular, small, 
surrounded by a clear zone 2 to 5 mm in 
diameter. Buff or reddish brown. 

Litmus milk: No growth. 

Indole not produced. 

Nitrites not produced from nitrates. 

Starch not hydrolyzed. 

No growth in media containing the usual 
carbohydrates. Cellulose and water-in- 
soluble dextrins are utilized. Filter paper 
strips in mineral solution develop reddish 
brown spots above the surface of the liquid. 
Solution becomes cloudy. Colonies enlarge 
and become viscous, and the paper becomes 
reddish. The filter paper does not break 
with moderate shaking but may be wound 
up in a slimy mass. In cellulose media a 
reddish, water-soluble pigment is produced. 

Yeast extract and nitrate are suitable 
nitrogen sources. 

Aerobic. 

Grows in a range from 22° to 35° C. 

Source: Isolated from soil. 

Habitat: Soil. 

30. Pseudomonas fragi (Eichholz, 1902) 
Huss, 1907, emend. Hussong et al., 1937. 
{Bacterium fragi Eichholz, Cent. f. Bakt., 
II Abt., 9, 1902, 425; Huss, Cent. f. Bakt., 
II Abt., 19, 1907, 661; Hussong, Long and 
Hammer, Iowa Agr. Exp. Sta. Res. Bull. 
225, 1937, 122.) 

fra'gi. L. neut.n. fragum strawberry; L. 
gen.n. fragi of the strawberry. 

Description from Hussong, Long and 
Hammer {loc. cit.). 

Rods, 0.5 to 1.0 by 0.75 to 4.0 microns, 
occurring singly, in pairs and in chains. 



FAMILY IV. PSEUDOMONADACEAE 



111 



Motile with a polar flagellum. Gram-nega- 
tive. 

Gelatin: Crateriform to stratiform lique- 
faction in 3 to 4 daj's. 

Agar colonies: Convex, glistening, gen- 
erally butyrous, occasionally viscid. Rough, 
smooth and intermediate forms are recog- 
nized in the description quoted. The rough 
forms are less proteolytic and less active 
in the hydrolysis of fats. 

Agar slant: Growth abundant, spreading, 
raised, white, shiny, generally butyrous. 
Sweet ester-like odor resembling that of the 
flower of the May apple. 

Broth: Turbidit}^ and sediment with a 
thin pellicle. 

Litmus milk: Acid ring followed by acid 
coagulum at surface. Complete coagulation 
in 2 to 3 weeks, some digestion. Characteris- 
tic Maj'-apple or strawberry odor. 

Potato : Growth echinulate to arborescent, 
raised, glistening, white, becoming brown- 
ish. 

Indole not produced. 

Nitrites not produced from nitrates. 

Ammonia produced from peptone. 

Hydrogen sulfide not produced. 

Acid from glucose and galactose, some- 
times arabinose. No acid from glycerol, 
inulin, lactose, fructose, maltose, mannitol, 
raffinose, salicin or sucrose. 

No acetylmeth3-lcarbinol produced. 

Fat is generally hydrolyzed (Nashif and 
Nelson, Jour. Dairy Sci., 36, 1953, 459-488). 

Aerobic. 

Grows from 10° to 30° C. No growth at 
37° C. Very sensitive to heat. 

Comment: Various names have been 
given this species. Hussong (Thesis, Iowa 
State College, 1932) thinks that these varie- 
ties are the result of dissociative action. 

Source: Isolated from milk and other 
dairy products, dairy utensils, water, etc. 

Habitat: Soil and water. Widely dis- 
tributed (Morrison and Hammer, Jour. 
Dairy Sci., ^4, 1941,9). 

31. Pseudomonas perolens (Turner, 
1927) Szybalski, 1950. {Achromobacter pero- 
lens Turner, Austral. Jour. Exp. Biol, and 
Med. Sci., 4, 1927, 57; Szybalski, Nature, 
165, 1950, 733.) 



pe.ro 'lens. L. v. perolere to emit a pene- 
trating odor; L. part. adj. perolens emitting 
an odor. 

Small, imperfect spheres and coccoid rods; 
occasionallj' longer rods with rounded ends; 
occur singly and in short chains. 0.3 by 0.4 
to 2.55 microns. Motile with a single polar 
flagellum. Gram-negative. 

Gelatin: Liquefied. 

Agar slants: Growth moderate, glisten- 
ing, raised, butyrous, spreading, with un- 
dulate border; whitish by reflected and 
semi-translucent by transmitted light. 

Broth: Turbid, with a flocculent sediment 
and a slight pellicle. 

Litmus milk: Acid, gradually decolorized, 
partial clotting. 

Blood serum: Liquefied. 

Potato: Growth thick, glistening, raised, 
brownish. 

Nitrites and ammonia produced from ni- 
trates. 

Indole not produced. 

Acid but no gas from glucose, fructose, 
galactose, glycerol, mannitol and arabinose. 
Sucrose, maltose, lactose, raffinose, dulcitol, 
salicin and inulin not utilized. 

Aerobic, facultative. 

Grows well at room temperature. No 
growth at 37° C. 

Distinctive characters : Produces a musty 
odor in eggs. Other varieties and species of 
Pseudomonas that produce the same odor 
have been described (Szybalski, loc. cit.). 
Resembles Pseudomonas fragi but produces 
a musty rather than a May-apple odor in 
media. 

Source: Isolated from eggs with a musty 
odor. 

Habitat: Musty eggs. 

32. Pseudomonas mephitica Claydon 
and Hammer, 1939. (Jour. Bact., 37, 1939, 
254.) 

me.phi'ti.ca. L. adj. mephiticus pestilen- 
tial (skunk-like) odor. 

Rods, 0.5 to 1.0 by 1.5 to 14.0 microns, 
occurring singly, in pairs and in chains. 
Actively motile with a polar flagellum. 
Gram-negative. 

Gelatin: Slow liquefaction. 

Agar colonies: Convex, circular, about 3 



112 



ORDER I. PSEUDOMONADALES 



mm in diameter, shiny, grajish white, en- 
tire, of the consistency of bread dough. 

Agar slant: Growth grayish white, 
wrinkled, echinulate. After 1 or 2 days a 
skunk-like odor develops. 

Broth: Turbid. Sediment. White pellicle. 

Potato: Growth echinulate, shiny, brown- 
ish. 

Litmus milk: A skunk-like odor develops 
in 1 to 2 days. Grayish blue surface ring in 
about 3 days. Alkaline in 7 to 10 daj^s. In 
two weeks complete reduction. Slight pro- 
teolysis and viscosity. 

Hydrogen sulfide not produced. 

Indole not produced. 

Nitrites produced from nitrates. 

Acid but no gas produced slowly from 
glucose, fructose, maltose and sucrose. No 
acid from arabinose, dextrin, galactose, 
glycerol, lactose, mannitol, raffinose or 
salicin. 

Aerobic, facultative. 

Optimum temperature, 21° C. Growth 
slight at 5° and 30°C. No growth at 37° C. 

Source: Several cultures isolated from 
butter having a skunk-like odor. 

Habitat: Presumably derived from the 
rinse water. 

33. Pseudomonas putrefaciens (Derby 
and Hammer, 1931) Long and Hammer, 
1941. (Achromobacter putrefaciens Derby 
and Hammer, Iowa Agr. Exp. Sta., Res. 
Bull. 145, 1931, 401; Long and Hammer, 
Jour. Bact., 41, 1941, 100.) 

pu.tre.fa'ci.ens. L. v. ptdrefacio to make 
rotten; L. part. adj. putrefaciens making 
rotten. 

Rods, 0.5 to 1.0 by 1.1 to 4.0 microns, 
occurring singly and in pairs. Motile with 
a single flagellum. Gram-negative. 

Gelatin stab: Rapid, saccate to strati- 
form liquefaction, with reddish brown sedi- 
ment in the liquefied portion. 

Agar colony: Circular, smooth, glisten- 
ing, slightly raised, somewhat transparent, 
with brownish tinge. 

Agar slant: Echinulate, slightly reddish 
brown, viscous. 

Broth: Turbid, with thin, gray pellicle 
and reddish brown sediment. 

Litmus milk: Rapid reduction and pro- 
teolysis with odor of putrefaction. 



Potato: Echinulate, smooth, glistening, 
viscous, reddish brown. 

Indole not produced. 

Nitrites are produced from nitrates. 

Acid from maltose and sucrose. No action 
on glucose, fructose, galactose, arabinose, 
lactose, raffinose, dextrin, inulin, salicin, 
amj'gdalin, glycerol, mannitol or sorbitol. 

Ammonia is formed. 

Aerobic, facultative. 

Optimum temperature, 21° C. No growth 
at 37° C. 

Source: Isolated from tainted butter. 

Habitat: Milk, cream, butter, water, soil 
and creamery equipment (Long and Ham- 
mer, loc. cit.; Claj'don and Hammer, op. 
cit., Res. Bull. 267^ 1939). 

34. Pseudomonas cohaerens (Wright, 
1895) Chester, 1901. {Bacillus cohaerens 
Wright, Mem. Nat. Acad. Sci., 7, 1895, 464; 
Pseudomonas cohaerea (sic) Chester, Man. 
Determ. Bact., 1901, 312.) 

co.hae'rens. L. part. adj. cohaerens co- 
hering, uniting together. 

Rods, occurring singly and in pairs, some- 
times in chains. Motile, possessing a polar 
flagellum. Gram-negative. 

Gelatin colonies : Circular, elevated, gray- 
ish, translucent, entire. Become white with 
an elevated, brownish, central nodule. 

Gelatin stab: Slow liquefaction. 

Agar slant: Elevated, grayish white, 
translucent, glistening, with irregular mar- 
gins. 

Broth: Turbid; coherent, wrinkled pel- 
licle which adheres to the walls of the con- 
tainer. 

Litmus milk: Alkaline, coagulated, slowly 
peptonized, litmus reduced. 

Potato: Thick, granular, translucent, 
spreading. 

Indole not produced. 

Grows at 25° C. 

Aerobic. 

Source: Isolated from water from the 
Schuylkill River. 

Habitat: Water. 

35. Pseudomonas ambigua (Wright, 
1895) Chester, 1901. (Bacillus amhiguus 
Wright, Memoirs Nat. Acad. Sci., 7, 1895, 



FAMILY IV. PSEUDOMONADACEAE 



113 



439; Chester, Man. Determ. Bact., 1901, 
308.) 

am.bi'gu.a. L. adj. anibiguus going 
about, hence uncertain. 

Small rods, with rounded ends, occurring 
singly, in pairs and in chains. Motile, pos- 
sessing a polar flagellum. Gram-negative. 

Gelatin colonies: Gray, translucent, 
slightly raised, irregular, radiate, with 
transparent margin. 

Gelatin stab: No liquefaction. 

Agar slant: Graj^, limited, entire. 

Broth: Turbid, with gray sediment. 

Litmus milk: Acid, slowly coagulated. 
Litmus reduced. 

Potato: Gray to creamj-, viscid, spread- 
ing. 

Indole produced. 

Aerobic, facultative. 

Optimum temperature, between 30° and 
35° C. 

Source: Isolated from water from the 
Schuylkill River. 

Habitat: Water. 

36. Pseudonionas oleovorans Lee and 

Chandler, 1941. (Jour. Bact., 4^, 1941, 378.) 

o.le.o'vor.ans. L. ole^^moil■, L. v. voro to 
destro}', consume; M.L. part. adj. oleovorans 
oil-consuming. 

Short rods, 0.5 by 0.8 to 1.5 microns, 
occurring singly and in pairs. Motile. Gram- 
negative. 

Gelatin stab: No liquefaction after 6 
weeks. 

Gelatin colonies : Up to 1 mm in diameter, 
fluorescent; similar to agar colonies. 

Surface agar colonies: After 24 hours 1 to 
2 mm in diameter, smooth, convex, shiny, 
opaque, creamy, fluorescent bj^ transmitted 
light. Edge entire in young colonies. 

Deep agar colonies: 0.5 by 1.0 to 1.5 mm, 
lens-shaped, buff-colored, not fluorescent. 

Agar slant: Growth raised, smooth, fluo- 
rescent, edge erose. 

Broth : After 24 hours, moderate turbidity 
with slight yellowish, viscid sediment. No 
pellicle or ring. No soluble pigment pro- 
duced. 

Litmus milk: No change. 

Indole not produced. 

Potato: Good growth. 

Nitrites are produced from nitrates. 



Starch is hydrol3'zed. 

No acid from glucose, lactose, sucrose, 
galactose, xylose, mannitol, salicin or 
glycerol. 

Equally good growth at 25° and 37° C. 

Aerobic. 

Distinctive character: The fluorescent 
quality of the colonies is not imparted to 
any of the artificial media used. 

Source: Isolated from cutting compound 
(oil-water emulsion) circulating in a ma- 
chine shop. The oil in this compound may 
be utilized as a sole source of energj'. 

Habitat: Probably oil-soaked soils. Abun- 
dant in cutting compounds. 

37. Pseudonionas arvilla Gray and 
Thornton, 1928. (Cent. f. Bakt., II Abt., 73, 
1928, 90.) 

ar.vil'.la. L. arvum a field; M.L. dim. noun 
arvilla a small field. 

Rods, 0.5 to 0.7 by 2.0 to 3.0 microns. 
Motile with one to five polar flagella. Gram- 
negative. 

Gelatin colonies: Circular, whitish, con- 
vex, smooth, glistening, lobate. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular or amoeboid, 
white to buff, flat to convex, smooth, glis- 
tening, opaque, entire. 

Agar slant: Filiform, whitish, convex, 
smooth, ringed, entire. 

Broth: Turbid. 

Nitrites not produced from nitrates. 

Starch not hydrolj'zed. 

Acid from glucose. 

Attacks naphthalene. 

Aerobic, facultative. 

Grows at 37° C. 

Source: Isolated from soil. 

Habitat: Soil. 

38. Pseudomonas daciinhae Gray and 
Thornton, 1928. (Cent. f. Bakt., II Abt., 73, 
1928, 90.) 

da.cun'hae. d'Acunha, place name. Island; 
M.L. gen. noun dacimhae of d'Acunha. 

Rods 0.5 to 0.8 by 1.5 to 3.0 microns. 
Motile with one to six polar flagella. Gram- 
negative. 

Gelatin colonies: Circular, whitish, 
raised, smooth, glistening, entire. 

Gelatin stab: No liquefaction. 



114 



ORDER I. PSEUDOMONADALES 



Agar colonies: Circular to amoeboid, 
white, flat, glistening, opaque, entire. 

Agar slant: Filiform, pale buff, raised, 
smooth, glistening, undulate. 

Broth: Turbid. 

Nitrites not produced from nitrates. 

Starch not hydrolyzed. 

No acid from carbohydrate media. 

Attacks phenol. 

Aerobic, facultative. 

Grows at 37° C. 

Source: Isolated from soil. 

Habitat: Soil. 

39. Pseudomonas desmolytica Gray 
and Thornton, 1928. (Cent. f. Bakt., II Abt., 
73, 1928, 90.) 

des.mo.ly'ti.ca. Gr. desmus bond; Gr. 
lyticus able to loose; M.L. adj. desmolyiiciis 
bond-loosening. 

Rods, 0.7 to 0.8 by 2.0 to 3.0 microns, 
occurring singly and in pairs. Motile, with 
one to five polar flagella. Gram-negative. 

Gelatin colonies: Circular, gray to buff, 
raised or umbonate. Smooth, glistening, 
entire. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular or amoeboid, 
whitish, flat or convex, smooth, translucent 
to opaque, entire. 

Agar slant: Filiform, pale buff, raised, 
smooth, undulate. 

Broth: Turbid. 

Nitrites often produced from nitrates. 

Starch not hydrolyzed. 

Acid usually produced from glucose. 

Attacks naphthalene. 

Aerobic, facultative. 

Grows at 35° C. 

Source: Isolated from soil. 

Habitat: Soil. 

40. Pseudomonas rathonis Gray and 
Thornton, 1928. (Cent. f. Bakt., II Abt., 73, 
1928, 90.) 

ra.tho'nis. RathoPark, place name; M.L. 
gen. noun rathonis of Ratho. 

Small rods, 0.5 to 1.0 by 1.0 to 3.0 microns, 
occurring singly and in pairs. Motile, with 
polar flagella. Gram-negative. 

Gelatin colonies: Circular, white, raised, 
smooth, glistening, undulate. 

Gelatin stab: No liquefaction. 



Agar colonies : Circular, buff, flat, smooth, 
glistening, entire. 

Agar slant: Filiform, pale buff, convex, 
smooth, glistening, undulate. 

Broth: Turbid; pellicle may form. 

Nitrites may be produced from nitrates. 

Starch may be hydrolyzed. 

Acid may be produced from glucose and 
glycerol. 

Attacks phenol and cresol at times, also 
naphthalene. 

Aerobic, facultative. 

Grows at 35° C. 

Source: Isolated from manure and soil. 

Habitat: Manure and soil. 

41. Pseudomonas salopia Gray and 
Thornton, 1928. (Pseudomonas salopium 
(sic) Gray and Thornton, Cent. f. Bakt., II 
Abt., 73, 1928, 91.) 

sa.lo'pi.a. Med.L. Salop Shropshire; 
M.L. adj. salopius of Shropshire. 

Rods, 0.7 to 1.0 by 1.0 to 3.0 microns, 
occurring singly and in pairs. Motile with 
one to six polar flagella. Gram-negative. 

Gelatin colonies: Circular, grayish buff', 
flat, rugose or ringed, translucent border. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular or amoeboid, 
white to buff, flat to convex, smooth, glis- 
tening, translucent border, entire. 

Agar slant: Filiform, whitish, raised, 
smooth, glistening, lobate. 

Broth: Turbid with pellicle. 

Nitrites not produced from nitrates. 

Starch not hydrolyzed. 

Acid from glucose and sucrose. 

Attacks naphthalene. 

Aerobic, facultative. 

Grows at 35° C. 

Source: Isolated from soil. 

Habitat: Soil. 

42. Pseudomonas cruciviae Gray and 
Thornton, 1928. (Cent. f. Bakt., II Abt., 73, 
1928, 91.) 

cru.ci'vi.ae. L. crux, cruets a cross; L. 
via a way; M.L. Crucivia Waycross, a place 
name. 

Rods, 1.0 by 1.0 to 3.0 microns, occurring 
singly and in pairs. Motile with one to five 
polar flagella. Gram-negative. 



FAMILY IV. PSEUDOMONADACEAE 



115 



Gelatin colonies: Circular, white, convex, 
smooth, undulate. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular or amoeboid, 
white to buff, flat to convex, smooth, entire. 

Agar slant: Filiform, pale buff, raised, 
smooth, undulate. 

Broth: Turbid. 

Nitrites not produced from nitrates. 

Starch not hj^droh-zed. 

No acid in carbohydrate media. 

Attacks phenol and m-cresol. 

Aerobic, facultative. 

Optimum temperature, between 30° and 
35° C. 

Source: Isolated from soil. 

Habitat: Soil. 

43. Pseudonionas stutzeri (Lehmann 
and Neumann, 1896) Kluyver, 1942. 
{Bacillus denitrificans II Burri and Stutzer, 
Cent. f. Bakt., II Abt., 1, 1895, 392; Bac- 
terium stutzeri Lehmann and Neumann, 
Bakt. Diag., 1 Aufl., 2, 1896, 237; Bacillus 
nitrogenes Migula, Syst. d. Bakt., 2, 1900, 
793; Pseudonionas stutzeri Kluyver, in 
Koningsberger, Leerb. d. algem. Plant- 
kunde, Scheltema and Holkema, Amster- 
dam, 2, 1942, 198; not Pseudonionas stutzeri 
Migula, Syst. d. Bakt., 2, 1900, 929.) 

stut'ze.ri. Named for Dr. A. Stutzer, one 
of the bacteriologists who originally de- 
scribed this species; M.L. gen. noun stutzeri 
of Stutzer. 

Description taken from van Niel and 
Allen (Jour. Bact., 64, 1952, 421). 

Rods, 0.5 to 0.8 by 1.0 to 3.0 microns. Mo- 
tile, possessing a single polar flagellum. 
Gram-negative. 

Gelatin and agar colonies: Strongly co- 
herent to media, dry consistency later be- 
coming mucoid, resemble craters with ele- 
vated ridges which often branch and merge, 
concentric zones, polygonal elements, 
granular. 

Gelatin: No liquefaction. 

Peptone and yeast agar: Good growth. 

Broth: Surface film on nitrate- or nitrite- 
free media which readily breaks up and pre- 
cipitates. 

Potato: Luxuriant, wrinkled, slimy, flesh- 
to peach-colored growth. 



Nitrates, nitrites, nitramines and N2O 
reduced to elemental nitrogen. 

Carbohj^drates : No growth when used as 
a carbon source in mineral media. 

Aerobic, facultative. 

Optimum pH, 7.0; growth even at pH 9.0. 

Optimum temperature, 35° C. 

Distinctive characters: Colony shape 
and consistency, mode and color of potato 
growth, ability to grow anaerobically in 
media with nitrate, nitrite, nitramine or 
N2O, producing foam. 

Source: Isolated from soil. 

Habitat: Found widely distributed in soil, 
manure, mud and stagnant water. 

44. Pseudomoiias tralucida Kellerman 
et al., 1913. (Kellerman, McBeth, Scales 
and Smith, Cent. f. Bakt., II Abt., 39, 1913, 
37.) 

tra.lu'ci.da. L. adj. frahicidus trans- 
parent. 

Rods 0.6 by 1.2 microns. Motile with one 
or two polar flagella. Gram-negative. 

Gelatin stab: No liquefaction. 

Agar slant: Moderate, flat, glistening, 
grayish growth. 

Broth: Turbid; granular sediment. 

Litmus milk: Acid, no coagulation. 

Potato: No growth. 

Indole not produced. 

Nitrites produced from nitrates. 

Ammonia not produced. 

Starch hydrolysis slight. 

Acid from glucose, maltose, lactose, su- 
crose, starch, glycerol and mannitol. 

Attacks cellulose. 

Aerobic, facultative. 

Optimum temperature, 37° C. Grows also 
at 20° C. 

Habitat: Soil. 

45. Pseudonionas lasia Fuller and Nor- 
man, 1943. (Jour. Bact., 46, 1943, 275.) 

la'si.a. Gr. adj. lasius hairy, rough, 
shaggy, woolly. 

Rods, 0.5 to 0.6 by 1.2 to 2.0 microns, 
usually occurring singly but sometimes in 
chains. Motile with a single polar flagellum. 
Gram-negative. 

Gelatin stab: No liquefaction. 

Starch agar colonies : Convex, pale 3'ellow, 
becoming cream color, entire, round. Sub- 



116 



ORDER I. PSEUDOMONADALES 



surface colonies look like small, woolly 
balls. 

Water-insoluble dextrin colonies: Col- 
onies grow below the surface and have a 
woolly appearance. Colonies are surrounded 
by clear zones. Become cream to pale yellow 
in color. 

Litmus milk : Unchanged except for reduc- 
tion of litmus at bottom of the tube. 

Indole not produced. 

Nitrites produced from nitrates. 

Starch hydrolyzed. 

Glucose, .xylose, maltose and starch read- 
ily utilized. Arabinose, galactose and gum 
arable feebly attacked. No acid formed in 
any of the above-mentioned substrates. 
Cellulose, cellulosan, water-soluble and 
water-insoluble cellulose, dextrins, hemi- 
cellulose and pectin readily attacked. Filter 
paper strips become pale yellowish in the 
area attacked. 

Peptone, yeast extract, nitrate and am- 
monia are suitable nitrogen sources. 

Aerobic. 

Grows between 22° and 35° C. 

Source: Isolated from soil. 

Habitat: Soil. 

46. Pseudonionas riboflavina Foster, 
1944. (Pseudotnonas riboflavinus (sic) Foster, 
Jour.Bact.,47, 1944,27; also see Jour. Bact., 
48, 1944, 97.) 

ri.bo.fla'vi.na. M.L. adj. riboflavinus 
pertaining to riboflavin. 

Thin rods of variable length. Motile. 
Gram-negative. 

Gelatin stab: No liquefaction. 

Yeast-extract agar colonies: Small, con- 
vex, smooth, transparent; slightly dentate 
edges. If glucose is added to the agar, 
copious quantities of polj'saccharides are 
formed. Presence of fructose, mannitol, su- 
crose, maltose, lactose, xylose and galactose 
also lead to polysaccharide formation. 

Yeast-extract glucose broth: Becomes so 
viscid that it scarcely flows. 

Milk: Soft curd forms. Slowly peptonized. 

Nitrites produced from nitrates. 

No acid or gas from fructose, mannitol, 
sucrose, maltose, lactose, xylose or galac- 
tose. Acetic acid oxidized. 

Acetylmethylcarbinol not produced. 

Urea, glycine, ammonium chloride or 



sodium nitrate cannot be used as substi- 
tutes for organic-nitrogen sources. Neither 
could 20 water-soluble accessory factors 
substitute for yeast extract in a synthetic 
mineral salts-glucose medium. 

No pigment produced in any medium. 

Starch not hydrolyzed. 

Optimum temperature, between 30° and 
33° C. 

Distinctive characters: In organic media 
containing a small amount of organic matter 
such as yeast extract or peptone and 0.05 to 
0.2 per cent riboflavin, the riboflavin is 
attacked and converted to lumichrome, 
which accumulates in the culture as lemon- 
yellow crystals. If riboflavin is not provided 
in the medium, appreciable quantities of it 
are synthesized by this organism. 

Source: Isolated from soil rich in ribo- 
flavin. 

Habitat: Unknown. 

47. Pseudomonas denitrificans Bergey 
et al., 1923. (Bacillus denitrificans fluorescens 
Christensen, Cent. f. Bakt., II Abt., 11, 
1903, 190; Bergey et al., Manual, 1st ed., 
1923, 131.) 

de.ni.tri'fi.cans. L. de away, from; L. 
nitruni soda; M.L. nitrate, niter; M.L. 
denitrifico to denitrify; M.L. part. adj. 
denitrificans denitrifying. 

Rods, 0.5 to 0.7 by 0.5 to 1.25 microns, 
occurring singly and in pairs in large, slimy 
masses. Motile. Gram-negative. 

Gelatin colonies: Small, circular, con- 
toured, raised, moist, pearly gray, glisten- 
ing. 

Gelatin stab: Whitish, lobed surface 
growth. Yellowish green growth in stab. No 
liquefaction. 

Agar colonies: Pearly white, circular, 
entire. 

Agar slant: Broad, whitish, contoured, 
moist, entire. 

Broth: Turbid, with thick, wrinkled 
pellicle. 

Litmus milk: Not coagulated. 

Potato: Reddish gray layer. 

Indole not produced. 

Nitrates reduced with production of 
nitrogen. 

Aerobic, facultative. 

Optimum temperature, 25° C. 



FAMILY IV. PSEUDOMONADACEAE 



117 



Source: Isolated from soil. 
Habitat: Soil. 

48. Pseudomonas indoloxidans Gray, 
1928. (Proc. Roy. Soc. London, B, 102, 1928, 
263.) 

in.dol.o'xi.dans. M.L. neiit.n. indolum 
indole; M.L. part. adj. oxidans oxidizing; 
from Gr. adj. oxys sharp, acid; M.L. part, 
adj. indoloxidans indole-oxidizing. 

Rods 1.0 by 3.0 microns. Motile with one 
to four polar flagella. Gram-negative 

Gelatin colonies: Round, convex, buff, 
smooth, glistening, erose. 

Gelatin stab: No liquefaction. 

Agar colonies: Round, convex, white, 
watery; transparent border, erose. 

Agar slant: Filiform, convex, whitish, 
smooth, glistening, undulate. 

Broth: Cloudy. 

Indole not produced. 

Nitrites produced from nitrates. No gas. 

No acid or gas from glucose, sucrose, lac- 
tose, maltose or glycerol. 

Starch not hydrolyzed. 

Phenol and m-cresol not attacked. 

Distinctive character: Indole decomposed 
in mineral salts agar medium with the for- 
mation of blue crystals of indigotin. 

Aerobic. 

Optimum temperature, between 25° and 
28° C. 

Source: Isolated from soil from Italian 
Tyrol. 

Habitat: Soil. 

49. Pseudomonas niira McBeth, 1916. 
(Soil Science, 1, 1916, 467.) 

mi'ra. L. adj. minis extraordinary. 

Rods 0.4 by 1.6 microns. Motile with a 
single polar flagellum. Gram-negative. 

Gelatin stab: Good growth. No liquefac- 
tion. 

Agar colonies : Circular, convex, grayish 
white, granular, lacerate. 

Agar slant: Moderate, flat, grayish white, 
somewhat iridescent. 

Broth: Turbid. 

Litmus milk: Alkaline. 

Potato : Moderate, grayish white, leathery 
growth. 

Indole not produced. 

Nitrites produced from nitrates. 



Ammonia is produced. 

No acid from glucose, maltose, lactose, 
sucrose, starch, glycerol or mannitol. 

Cellulose decomposed. Pllter paper strips 
disintegrated at surface of liquid medium. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Source: Isolated from soil. 

Habitat: Soil. 

50. Pseudomonas nigrifaciens White, 
1940. (Scientific Agriculture, 20, 1940, 643.) 

ni.gri.fa'ci.ens. L. niger black; L. v. 
Jacio to make; M.L. part. adj. nigrofaciens 
blackening. 

Rods, 0.5 by 1.5 to 2.0 microns, occurring 
singly or in pairs and having rounded ends. 
Actively motile with a single polar flagel- 
lum. Gram-negative. 

Gelatin stab: Pigmented surface growth 
after 24 hours. Slight crateriform liquefac- 
tion changing to saccate. 

Agar colonies: Circular, convex, smooth, 
glistening, entire, 2 to 4 mm in diameter. 
Slight fluorescence in early stages. The me- 
dium assumes a brownish color. 

Agar slant: Growth filiform, smooth, 
moist, glistening, with blackish pigmenta- 
tion at 4° and 15° C. in 48 hours, the medium 
turning brownish. Slight fluorescence in 
early stages. 

Broth: Turbid after 24 hours. After 5 to 6 
days a black ring and then a pellicle forms, 
later a black sediment. Medium turns 
brown. 

Litmus milk: A black ring appears after 3 
days at 15° C. followed by a pellicle. Litmus 
is reduced. Alkaline reaction. No coagula- 
tion. Digested with a putrid odor. 

Potato: No growth, even in presence of 
1.5 per cent salt. 

Nitrites not produced from nitrates in 7 
days. No gas produced. 

Starch is hydrolyzed. Natural fats not 
hydrolj'zed. 

Alkaline reaction produced in sucrose, 
maltose, lactose, glucose, mannitol and 
raffinose broth (pH 8.2). No gas produced. 

Ammonia produced in peptone broth. 

Aerobic. 

Optimum pH, 6.8 to 8.4. 

Temperature relations: Minimum, 4° C. 
Optimum, 25° C. Maximum, 33° to 35° C. 



118 



ORDER I. PSEUDOMONADALES 



Distinctive characters : No or slow growth 
in culture media in the absence of salt. 
Maximum growth and pigmentation ap- 
pears with 1.5 and 2.5 per cent salt. Opti- 
mum pigmentation occurs at 4° and 15° C. 
Pigment insoluble in chloroform. 

Source: Several cultures isolated from 
samples of discolored butter. 

Habitat : Causes a black to reddish brown 
discoloration of print butter. Evidently 
widely distributed in nature. 

51. Pseudonionas ichthyodermis (Wells 
and ZoBell, 1934) ZoBell and Upham, 1944. 
(Achromobacter ichthyodermis (sic) Wells and 
ZoBell, Proc. Nat. Acad. Sci., £0, 1934, 123; 
ZoBell and Upham, Bull. Scripps Inst. 
Oceanography, 5, 1944, 246 and 253.) 

ich.thy.o.der'mis. Gr. ichthys fish; Gr. 
derma skin; M.L. ichthyodermis fish skin. 

Small rods, 0.9 to 1.3 by 3.0 to 5.0 microns, 
occurring singlj^ and in pairs. Motile, with 
a tuft of polar flagella. Pleomorphic forms 
predominate in old cultures. Encapsulated. 
Gram-negative. 

Requires sea water following initial iso- 
lation. The following differential media are 
prepared with sea water: 

Agar colonies: Glistening, colorless, con- 
vex, circular, 2 to 4 mm in diameter. 

Agar slants: Abundant, filiform, raised, 
smooth, opalescent growth. 

Gelatin tube : Rapid crateriform liquefac- 
tion complete in 5 days at 18° C. 

Sea-water broth: Turbidity, with pellicle, 
little granular sediment and no odor. 

Milk: No growth. 

Potato : No growth unless dialyzed in sea 
water. Then fair growth with no pigment. 

Acid from glucose, sucrose and mannitol 
but not from lactose or glycerol. 

Starch hydrolyzed. 

Ammonia liberated from peptone, but no 
hydrogen sulfide produced. 

Indole formed in tryptophane sea-water 
broth. 

Nitrites produced from nitrates. 

Optimum temperature, between 25° and 
30° C.; 37° C. incubation will kill recently 
isolated organisms. 

Aerobic, facultative. 

Source: Isolated from diseased kilifish 
{Fundnlus parvipinnis) . 



Habitat: Skin lesions and muscle tissue of 
infected marine fish. 

52. Pseudonionas niarinoglutinosa 

(ZoBell and Allen, 1935) ZoBell, 1943. 
{Achromobacter viarinoglutinosus (sic) Zo- 
Bell and Allen, Jour. Bact., 29, 1935, 246; 
ZoBell, Jour. Bact., ^6, 1943, 45.) 

ma.ri.no.glu.ti.no'sa. L. marinus ma- 
rine; L. glutinosus full of glue, viscous; M.L. 
adj. marinoglutinosus . Meaning obscure. 

Short rods, 0.7 to 1.0 by 1.8 to 2.4 microns, 
with rounded ends, occurring singly, in pairs 
and in clumps. Motile with polar flagella. 
Staining granular. Encapsulated. Gram- 
negative. 

Gelatin stab: Moderate filiform growth f; 
with slight napiform liquefaction. No pig- 
ment. 

Agar colonies: Round with concentric 
circles and crinkled radial lines, 1.5 to 5.0 
mm in diameter. No pigment. 

Agar slant: Moderate, filiform, flat. 
Butyrous consistency. 

Broth: Moderate clouding, marked ring, 
adherent film of growth on test tube wall, 
flaky sediment. 

Milk: No growth. 

Potato: No growth. 

Indole not produced. 

Nitrites not produced from nitrates. 

Hydrogen sulfide and ammonia produced 
from Bacto-tryptone. 

Acid but no gas from xylose and dextrin. 
No acid from glucose, lactose, sucrose or 
mannitol. 

Starch is hydrolj'zed. 

Optimum temperature, between 20° and 
25° C. 

Aerobic, facultative. 

Source : Isolated from sea water. 

Habitat: Sea water. 

53. Pseudonionas nienibranoforniis 

(ZoBell and Allen, 1935) ZoBell, 1943. 
{Achromobacter membranoformis ZoBell and 
Allen, Jour. Bact., £9, 1935, 246; ZoBell, 
Jour. Bact., 46, 1943, 45.) 

mem. bra. no. for 'mis. L. membrana a 
membrane; L. forma appearance; M.L. adj. 
membranoform is membranous . 

Reds, 0.9 to 1.2 by 3.5 to 4.8 microns, oc- 
curring singly and in pairs. Motile with 



FAMILY IV. PSEUDOMONADACEAE 



119 



lophotrichous flagella. Encapsulated. Gram- 
negative. 

Gelatin stab : Growth filiform, best at top, 
1 with slow crateriform liquefaction. 

Agar colonies: Circular, 1.0 to 2.5 mm, 
with crinkled surface. 

Agar slant: Moderate, beaded, raised 
growth. ]\Iembranous consistency. Becomes 
browned with age. 

Broth: Slight turbidity, flocculent sedi- 
ment, film of growth on walls of test tube. 

IMilk: No growth. 

Potato: No growth. 

Indole not produced. 

Nitrites not produced from nitrates. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, sucrose, 
dextrin and mannitol. No acid from lactose 
or xylose. 

Starch not hydrolyzed. 

Optimum temperature, between 20° and 
25° C. 

Aerobic. 

Source: Isolated from sea water. 

Habitat: Sea water. 

54. Pseudonionas gelatica (Gran, 1902) 
Bergey et al., 1930. {Bacillus gelaticus Gran, 
Bergens Museums Aarbog., 1902, 14; Bergey 
et al.. Manual, 3rd ed., 1930, 175.) 

ge.la'ti.ca. L. part. adj. gelatns frozen, 
congealed, jellied; M.L. adj. gelaticus re- 
sembling hardened gelatin. 

Rods, with rounded ends, 0.6 to 1.2 by 1.2 
to 2.6 microns, occurring singly, in pairs, 
and sometimes in short chains. Motile, type 
of flagellation not recorded. Gram -negative. 

All media prepared with 3 per cent salt. 

Fish-gelatin colonies: Circular, trans- 
parent, glistening, becoming brownish in 
color. 

Fish-gelatin stab: Liquefaction infun- 
dibuliform. Two varieties are recognized: 
one produces a green fluorescence; the other 
does not produce a water-soluble pigment. 

Sea-weed agar colonies: Circular, flat, 
entire, glistening, grayish blue center with 
reddish brown periphery. Liquefied. 

Fish-agar slant: Flat, transparent streak, 
with undulate margin, reddish brown to 
grayish white. 

Broth: Turbid with flocculent pellicle 
and grayish yellow sediment, viscid. 



Indole not produced. 

Nitrites not produced from nitrates. 

Starch hj^drolyzed. 

No action on sugars. 

Aerobic, facultative. 

Temperature relations : Optimum temper- 
ature, between 20° and 25° C. Maximum, 
between 30° and 32° C. Minimum, 0° C. 

Distinctive character: Requires 3 to 4 per 
cent salt for growth. 

Source : Isolated from sea water from the 
Norwegian coast. 

Habitat: Probably associated with the de- 
composition of algae in coastal waters. 

55. Pseudomonas calcis (Drew, 1912) 
Kellerman and Smith, 1914. (Bacterium 
calcis Drew, Yearbook Carnegie Inst. 
Wash., 11, 1912, 136; Kellerman and Smith, 
Jour. Wash. Acad. Sci., 4, 1914, 400.) 

cal'cis. L. fem.noun calx, calcis limestone, 
chalk; L. calcis of limestone. 

Rods, 1.1 by 1.5 to 3.0 microns, usually 
single but may form long chains. Actively 
motile with one polar flagellum. Gram- 
negative. 

Grows best in sea water or 3 per cent salt 
media. Deposits CaCOs . 

Agar colonies: Circular, with finely ir- 
regular outline, granular appearance, ele- 
vated, spreading; old colonies having 
brownish tinge in center. 

Gelatin stab: Infundibuliform liquefac- 
tion. 

Gelatin colonies : Small, with liquefaction. 

Broth: Good growth especially in pres- 
ence of potassium nitrate, peptone or cal- 
cium malate. 

Acid from glucose, mannitol and sucrose 
but not from lactose. 

Nitrates reduced to nitrites and am- 
monia. 

Aerobic, facultative. 

Optimum temperature, between 20° and 
28° C. 

Habitat: Sea water and marine mud. 

56. Pseudomonas calciprecipitans 

Molisch, 1925. (Cent. f. Bakt., II Abt., 65, 
1925, 130.) 

cal.ci. pre. ci'pi. tans. L. calx, calcis lime; 
L. praecipito to throw down; M.L. part. adj. 
calciprecipitans lime-precipitating. 



120 



ORDER I. PSEUDOMONADALES 



Thin rods, 0.5 to 0.8 by 1.5 to 3.6 microns, 
with rounded ends, often staining irregu- 
larly. Motile, with one polar flagellum. 
Gram-negative. 

Gelatin colonies: Circular, light brown in 
color (large colonies show CaCOg crystals). 

Gelatin stab : Surface growth with filiform 
growth in depth. Liquefaction starts at 
bottom. 

Agar colonies (sea water) ; Grayish white, 
glistening. In two to three weeks crystals 
of calcium carbonate form in the agar. 

Agar slant: Slight, whitish surface 
growth becoming thick, spreading, glisten- 
ing, with abundant CaCOs crystals in 
medium. 

Ammonia formed. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Source : Isolated from sea water. 

Habitat: Sea water. 

56a. Pseudomonas halestorga Elazari- 
Volcani, 1940. (Pse2idomonas halestorgus (sic) 
Elazari-Volcani, Studies on the Microflora 
of the Dead Sea. Thesis, Hebrew University, 
Jerusalem, 1940, VIII and 82.) 

hal.e'stor.ga. Gr. noun hale salt water; 
Gr. adj. storgus loving; M.L. adj. halestorgus 
salt-water-loving. 

Rods, the length of which varies greatly 
depending on the concentrations of salt : at 
3 to 24 per cent, they are usually 0.5 bj^ 1.3 
to 4.0 microns, occurring singly and in pairs; 
in 0.5 and 30 per cent salt and in Dead Sea 
water, the rods are usually very long, 
twisted threads. Motile by means of a single, 
polar flagellum. Gram-negative. 

Gelatin stab (12 per cent salt, 1 per cent 
proteose peptone, 15 per cent gelatin) : Fili- 
form, very slight infundibuliform liquefac- 
tion after six weeks. 

Agar colonies (12 per cent salt, 1 per cent 
proteose peptone, 2 per cent KNO3) : Circu- 
lar, smooth, entire, slightly convex, glisten- 
ing, slightly transparent, grayish. 

Agar slant (12 per cent salt, 1 per cent 
proteose peptone, 2 per centKNOa) : Moder- 
ate, filiform, raised, smooth, slightly trans- 
parent, grayish growth. 

Broth (12 per cent salt, 1 per cent pej)- 
tone) : Very turbid; whitish pellicle is 
formed. 



Indole not produced. 

No acid or gas from glucose, fructose, 
galactose, mannose, lactose, sucrose, mal- 
tose, arabinose, xylose, rafEnose, inulin, 
dextrin, glycerol, mannitol or salicin. 

Starch not hydrolyzed. 

Nitrites are produced from nitrates; no 
gas is produced. 

Aerobic. 

Optimum temperature, 30° C. 

Salt tolerance: Halotolerant, growing 
slightly in 0.5 per cent salt, strongly in 3 to 
30 per cent salt and moderately in Dead Sea 
water. 

Source: Isolated from the water of the 
Dead Sea. 

Habitat: Found in places where the salt 
content of water is high. 

57. Pseudomonas iridescens Stanier, 
1941. (Jour. Bact., 4S, 1941, 542.) 

ir.id.es'cens. Gr. fem.noun iris, -idis the 
rainbow; M.L. part. adj. iridescens showing 
colors of the rainbow. 

Rods, 0.2 to 0.3 by 1.5 to 7.0 microns, 
average length 5.0 to 6.0 microns, occurring 
singly. Non-motile. Gram-negative. 

Sea water gelatin stab: Filiform growth. 
Liquefaction by some strains. 

Sea water agar colonies: Concave, 2 to 3 
mm in diameter, smooth, glistening, trans- 
lucent, pale j^ellow, edge irregular. After 2 
to 3 days a marked iridescence. Later 
colonies rough, opaque, bright yellow, 
sunken central portion with translucent 
peripher3^ 

Sea water agar slant: Growth spreading, 
smooth, glistening, translucent, pale yel- 
low, iridescent, butyrous. 

Sea water broth: Turbid, light yellow, 
granular pellicle. 

Indole not produced. 

Nitrites not produced from nitrates. 

Hydrogen sulfide not produced. 

Catalase-positive. 

Urease-negative. 

Acid from xylose, glucose, galactose, 
lactose, maltose, sucrose and cellobiose. No 
acid from arabinose. Starch and cellulose 
are attacked. 

Aerobic. 

Temperature relations: Optimum, 23° C. 
Minimum, 5° C. Maximum, 30° C. 



FAMILY IV. PSEUDOMONADACEAE 



121 



Salt range: 0.25 to 6.0 percent. Optim\im, 
1.0 to 4.0 per cent. 

Source: Sea water. 

Habitat: Common along the coast of the 
North Pacific. 

58. Pseudomonas beijerinckii Hof, 
1935. (Travaux botaniques neerlandais, 32, 
1935, 152.) 

bei.jer.inck'i.i. M.L. gen. noun heije- 
rinckii of Beijerinck; named for Prof . M. W. 
Beijerinck of Delft, Holland. 

Small rods. Motile with polar flagelhi. 

Gelatin: No liquefaction. 

Indole not produced. 

Nitrites produced from nitrates by four 
out of six strains. 

Cellulose not decomposed. 

Acid from glucose. In yeast-water with 2 
per cent glucose and 12 per cent NaCI, no gas 
is produced. 

Pigment production: Insoluble purple pig- 
ment produced but not in all media; is lo- 
calized markedl}^; reduced oxygen tension 
necessary; optimum pH, 8.0; not produced 
in yeast-water or in peptone-water; pro- 
duced only when grown in extracts of beans 
or some other vegetable. 

Aerobic. 

Source: Six strains isolated from beans 
preserved with salt. 

Habitat: Causes purple discoloration of 
salted beans. 

59. Pseudomonas aceris (Ark, 1939) 
Starr and Burkholder, 1942. (Phytomonas 
aceris Ark, Phytopath., 29, 1939, 969; Starr 
and Burkholder, Phytopath., 32, 1942, 601.) 

a'ce.ris. L. acei- the maple; L. neut. 
gen. noun aceris of the maple. 

Rods 0.3 to 0.8 by 0.8 to 2.5 microns. 
Motile, with 1 to 2 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced. 

Gelatin: Liquefied. 

Beef -extract-peptone agar: Colonies are 
grayish white, appearing in 24 hours. 

Broth: Turbid. 

Milk: Clearing with no coagulation. 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Indole not produced. 

Hydrogen sulfide not produced. 



Acid from glucose, fructose, galactose, 
arabinose, xylose, sucrose, maltose, lactose, 
raffinose, mannitol, glycerol and dulcitol. 

Slight growth in broth plus 6 per cent salt 
(Burkholder). 

Optimum temperature, between 13° and 
31° C. 

Source : From diseased leaves of the large 
leaf maple, Acer niacrophyllum. 

Habitat: Causes a disease of Acer spp. 

60. Pseudomonas angulata (Fromme 
and Murray, 1919) Holland, 1920. (Bac- 
terium angulatum Fromme and Murray, 
Jour. Agr. Res., 16, 1919, 219; Holland, Jour. 
Bact.,5, 1920,224.) 

ang.u.la'ta. L. part. adj. angulatus wdth 
angles, angular. 

Description from Clara (Cornell Agr. 
Exp. Sta. Mem. 159, 1934, 24). 

Rods 0.75 to 1.5 by 1.5 to 3.0 microns. 
Motile, with 1 to 6 polar flagella. Gram- 
negative. 

Gelatin: Liquefied. 

Green fluorescent pigment produced. 

Beef-extract agar colonies: Dull white, 
circular, raised, smooth and glistening. 

Broth: Turbid and greenish in 36 hours. 

Milk: Alkaline. 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Indole not produced. 

Hydrogen sulfide not produced. 

Lipolytic action negative (Starr and 
Burkholder, Phytopath., 32, 1942, 601). 

Acid but no gas from glucose, galactose, 
fructose, mannose, arabinose, xylose, su- 
crose and mannitol. Alkaline reaction from 
salts of citric, malic, succinic and tartaric 
acids. Rhamnose, maltose, lactose, raffinose, 
glycerol, salicin, and acetic, lactic and 
formic acids are not fermented. 

Starch not hydrolyzed. 

Slight growth in broth plus 5 to 6 per cent 
salt (Burkholder). 

Aerobic, facultative. 

Relationship to other species: Braun 
(Phytopath., 27, 1937, 283) considers this 
species to be identical in culture with Pseu- 
domonas tabaci, but they differ in the type of 
disease they produce. 

Source : Isolated by Fromme and Murray 
from small angular leaf spots on tobacco. 



122 



ORDER I. PSEUDOMONADALES 



Habitat : Causes the angular leaf spot of 
tobacco {Nicotiana tahacum). 

61. Pseudomonas aptata (Brown and 
Jamieson, 1913) Stevens, 1925. {Bacterium 
aptatum Brown and Jamieson, Jour. Agr. 
Res., 1, 1913, 206; Stevens, Plant Disease 
Fungi, New York, 1925, 22.) 

ap.ta'ta. L. part. adj. aptahis adapted. 

Rods 0.6 by 1.2 microns. Motile, with bi- 
polar fiagella. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Agar slants: Moderate growth along 
streak, filiform, whitish, glistening. 

Broth: Turbid, with formation of a pel- 
licle. 

Milk: Becomes alkaline and clears. 

Nitrites not produced from nitrates. 

Indole not produced in 10 daj's. Slight 
amount found later. 

Hydrogen sulfide not produced. 

Acid from glucose, galactose and sucrose. 
No acid from lactose, maltose or mannitol 
(Paine and Banfoot, Ann. Appl. Biol., 11, 
1924, 312). 

Starch not hydrolyzed. 

Slight growth in broth plus 7 per cent salt 
(Burkholder) . 

Temperature relations: Optimum, be- 
tween 27° and 28° C. Minimum, below 1° C. 
Maximum, between 34° and 35° C. 

Aerobic. 

Source : Isolated from diseased nasturtium 
leaves from Virginia and diseased beet 
leaves from Utah. 

Habitat: Pathogenic on sugar beets, nas- 
turtiums and lettuce. 

62. Pseudomonas primulae (Ark and 
Gardner, 1936) Starr and Burkholder, 1942. 
{Phytomonas primnlae Ark and Gardner, 
Phytopath., S6, 1936, 1053; Starr and Burk- 
holder, Phytopath., 32, 1942, 601.) 

pri'mu.lae. L. dim. adj. prinmlus the first; 
M.L. fem.noun Primula generic name; 
M.L. gen. noun primulae of Primula. 

Rods 0.51 to 0.73 by 1.0 to 3.16 microns. 
Motile, with a polar flagellum. Gram-nega- 
tive. 

Green fluorescent pigment produced in 
culture. 



Gelatin: Liquefied. 

Agar colonies: Round, convex, smooth, 
glistening, j-ellowish. 

Milk: Coagulated. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolj'tic (Starr and Burkholder, 
Phytopath., 32, 1942, 601). 

Acid but no gas from glucose, lactose, su- 
crose, maltose, galactose, arabinose, glyc- 
erol, dulcitol and mannitol. Starch not 
hydrolyzed. 

Growth in broth plus 5 per cent salt. 

Temperature relations : Optimum between 
19° and 22° C. Minimum, 10° C. Maximum, 
34° C. 

Optimum pH between 6.8 and 7.0. Mini- 
mum, between 4.5 and 5.0. 

Aerobic, facultative. 

Source : Isolated from leaf -spot of Primula 
polyantha. 

Habitat: Pathogenic on Primula spp. 

63. Pseudomonas viridilivida (Brown, 
1915) Holland, 1920. {Bacterium viridilivi- 
dum Brown, Jour. Agr. Res., 4, 1915, 475; 
Holland, Jour. Bact., 5, 1920, 225.) 

vi.ri.di.li'vi.da. L. viridis green; L. livi- 
dus blue; M.L. adj. viridilividus greenish 
blue. 

Rods 1.0 to 1.25 by 1.25 to 3.0 microns. 
Motile, with 1 to 3 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Slow liquefaction. 

Beef agar colonies: Cream- white, round, 
smooth, translucent, edges entire. 

Broth: Turbid, becomes lime-green. 

Milk: Alkaline and clears. 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Indole produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., S^, 1942,601). 

Acid from glucose and sucrose (Burk- 
holder). 

Grows well in 4.5 per cent salt. Grows in 7 
per cent salt (Burkholder). 

Temperature relations: Minimum, 1.5° C. 
Maximum, 34.5° C. 
Aerobic. 



FAMILY IV. PSEUDOMONADACEAE 



123 



Source: Isolated from diseased lettuce 
from Louisiana. 

Habitat: Pathogenic on lettuce, Lactuca 
saliva. 

64. Pseudonionas delphinii (Smith, 
1904) Stapp, 1928. {Bacillus delphinii Smith, 
Science, 19, 1904, 417; Stapp, in Sorauer, 
Handbuch der Pflanzenkrankheiten, 2, 5 
Aufl., 1928, 106.) 

del.phi'ni.i. Gr. delphinium the larkspur; 
ALL. dim. neut. noun Delphinium generic 
name; M.L. gen. noun delphinii of larkspur. 

Rods 0.6 to 0.8 by 1.5 to 2.0 microns. 
Chains present. Motile, with 1 to 6 polar 
flagella. Encapsulated. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Beef agar slants: Growth thin, smooth, 
shining, transparent, margins entire, crys- 
tals. Agar becomes dark brown. 

Broth: Turbid in 24 hours with delicate 
pellicle. 

Milk: Becomes alkaline and clears. 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Lidole not produced. 

Hydrogen sulfide not produced. 

Lipolytic action negative (Starr and 
Burkholder, Phytopath., 32, 1942, 601). 

Acid from glucose, galactose and fructose; 
slight acid from sucrose. No acid from lac- 
tose, maltose, glj'cerol or mannitol. 

Starch: Hydrolysis feeble. 

Weak growth in broth plus 4 per cent salt. 

Optimum pH, 6.7 to 7.1. pH range, 5.6 to 
8.6. 

Temperature relations: Optimum, 25° C. 
Minimum, 1° C. or less. Maximum, 30° C. 

Source: Isolated from black spot of del- 
phinium. 

Habitat: Pathogenic on delphinium caus- 
ing a black spot in the leaves. 

65. Pseudonionas cepacia Burkholder, 
1950. (Phytopath., J^0, 1950, 116.) 

ce.pa'ci.a. L. fem.noun caepa or cepa 
onion; M.L. adj. cepacius of or like onion. 

Rods, 0.8 by 1.0 to 2.8 microns, occurring 
singly or in pairs. Motile, with 1 to 3 polar 
flagella. Gram-negative. 

Gelatin: Slow liquefaction. 



Beef -extract-peptone agar: Slants sulfur- 
yellow, filiform, butyrous to slightly viscid. 
Most cultures appear rough. Yellow to 
yellow-green pigment diffuses into medium 
about the colony. 

Potato dextrose agar: Pale yellow. No 
change in medium. 

Broth: Turbid in 24 hours; yellow pellicle. 

Milk: Litmus reduced. Medium clears and 
becomes tan with a yellow pellicle. 

Krumwiede's Triple sugar agar: Growth 
very abundant, j-ellow-green and extremely 
wrinkled; medium becomes red. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, fructose, 
lactose, maltose, sucrose, arabinose, xylose, 
glycerol, mannitol and salicin; alkaline re- 
action from sodium salts of citric, hippuric, 
malonic and tartaric acids. Growth is slight 
in rhamnose. 2 per cent ethyl alcohol jiot 
utilized. 

Starch not hydrolj^zed. 

Sodium ammonium pectate medium not 
liquefied. 

Methyl red test negative; acetylmethyl- 
carbinol not produced. 

Growth in 3 per cent but not in 5 per cent 
salt. 

Temperature relations: Optimum, 30° C. 
Minimum, between 6° and 9° C. Maximum, 
42° C. 

Aerobic. 

Source: Seven isolates from different 
onion bulbs collected in New York State. 

Habitat: Pathogenic on onions. Allium 
cepa. 

66. Pseudonionas apii Jagger, 1921. 
(Jour. Agr. Res., 21, 1921, 186.) 

a'pi.i. L. apium celery; M.L. neut. noun 
Apium generic name of celery; M.L. neut. 
gen. noun apii of celery. 

Description from Clara (Cornell Agr. 
Exp. Sta. Mem. 159, 1934, 24). 

Rods 0.75 to 1.5 by 1.5 to 3.0 microns. 
Motile with a polar flagellum. Gram-nega- 
tive. 

Green fluorescent pigment produced in 
various media. 

Gelatin: Liquefied. 

Beef -extract agar colonies: Circular, 



124 



ORDER I. PSEUDOMONADALES 



glistening, smooth, edges entire. Grayish 
white with bluish tinge. 

Broth: Turbid in 36 hours. Pellicle 
formed. 

Milk: Becomes alkaline. No curd. 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, galactose, 
fructose, mannose, arabinose, xylose, su- 
crose, mannitol and glycerol. Alkaline reac- 
tion from salts of acetic, citric, malic and 
succinic acids. Rhamnose, maltose, lactose, 
raffinose salicin, and formic, lactic and 
artaric acids are not utilized. 

Starch not hydrolyzed. 

Aerobic, facultative. 

Distinctive character: Pathogenicity ap- 
pears limited to celery. 

Source: Jagger isolated this repeatedly 
from diseased celery leaves. 

Habitat: Pathogenic on celery, Apiutn 
graveolens. 

67. Pseudomonas asplenii (Ark and 
Tompkins, 1946) Savulescu, 1947. (Phj/to- 
monas asplenii Ark and Tompkins, Phyto- 
path., 36, 1946, 760; Savulescu, Anal. Acad. 
Romane, III, 2^, 1947, 11.) 

a.sple'ni.i. Gr. neut.noun asplenum 
spleenwort; M.L. neut.noun Asplenium 
generic name; M.L. gen.noun asplenii of 
Asplenium. 

Rods 0.3 to 0.5 by 1.2 to 2.4 microns. 
Motile, with 1 to 3 polar flagella. Gram- 
negative. 

Gelatin: Liquefied. 

Beef -extract-peptone agar slants : Grayish 
white with fluorescence in the medium. 

Potato-dextrose-peptone agar: Growth 
rapid, heavy, strongly grayish white, 
butyrous; medium darkens with age. 

Nutrient broth: Turbid in 24 hours; no 
pellicle. 

Milk: No curd. 

Indole not produced. 

Nitrites not produced from nitrates. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, galactose, 
fructose, arabinose, xylose, maltose and 
sucrose. Slight acidity in lactose after long 
incubation; no acid in rafiinose. 



Starch not hydrolyzed. 

Growth good in Fermi's, Cohn's and 
Uschinsky's solutions. 

Temperature relations : Optimum between 
22° and 30° C. Minimum, 1° C. Maximum, 
34° C. 

Source : Six isolates and 3 reisolates from 
lesions on the bird's nest fern. 

Habitat: Pathogenic on the fern, Asple- 
nium nidus. 

68. Pseudomonas berberidis (Thorn- 
berry and Anderson, 1931) Stapp, 1935. 
(Phytomonas berberidis Thornberry and An- 
derson, Jour. Agr. Res., 43, 1931, 36; Stapp, 
Bot. Rev., 1, 1935,407.) 

ber.be'ri.dis. M.L. Berberis generic name 
of barberry; M.L. fem. gen. noun berberidis 
of barberry. 

Rods, 0.5 to 1.0 by 1.5 to 2.5 microns, oc- 
curring singly or in pairs. Motile with 2 to 4 
polar flagella. Encapsulated. Gram-negative 
(Burkholder); not Gram-positive as stated 
in original description. 

Green fluorescent pigment produced in 
culture (Burkholder). 

Gelatin: Not liquefied. 

Glucose agar slants: Growth moderate, 
filiform at first, later beaded, raised, 
smooth, white. Butyrous in consistency. 

Milk: Becomes alkaline. No other change. 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 3^, 1942, 601). 

Acid from glucose, galactose and sucrose. 
Maltose and rhamnose not utilized (Burk- 
holder). 

No gas from carbohydrates. 

Starch not hydrolyzed. 

Temperature relations: Optimum, 18° C. 
]\Iinimum, 7° C. Maximum, 30° C. 

Aerobic. 

Source: Repeated isolations from leaves 
and twigs of barberry. 

Habitat: Pathogenic on barberry, Berberis 
thnnbergerii and B. vulgaris. 

69. Pseudomonas coronafaeiens (El- 
liott, 1920) Stevens, 1925. {Bacterium corona- 



FAMILY IV. PSEUDOMONADACEAE 



125 



faciens Elliott, Jour. Agr. Res., 19, 1920, 153; 
Steven.s, Plant Disease Fungi, 1925, 27.) 

co.ro.na.fa'ci.ens. L. corona crown; L. 
facio to make; M.L. part. adj. coronafaciens 
halo-producing. 

Rods, 0.65 by 2.3 microns, occurring in 
chains. Motile with polar flagella. Encapsu- 
lated. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Slow liquefaction. 

Nutrient agar colonies: White, becoming 
irregularly circular, flat with raised mar- 
gins. 

Broth : Slight turbidity in 24 hours. Heavy 
pellicle formed. 

Milk: Alkaline. A soft curd formed fol- 
lowed by clearing. Curd sometimes absent. 

Test for nitrites produced in nitrate broth 
negative or faint (Burkholder and Starr, 
Phytopath., 38, 1948, 498). 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 32, 1942, 601). 

Acid but no gas from glucose and sucrose. 
Starch hj^drolysis slight. 

Slight growth in broth plus 2 per cent salt. 

Temperature relations: Optimum between 
24° and 25° C. Minimum, 1° C. Maximum, 
31° C. 

Comment: A variety pathogenic on 
brome-grass, Bromus inermis, has been de- 
scribed by Reddy and Godkin (Phytopath., 
IS, 1923, 81). Produces water-soaked spots 
which are dark purple in color. Has been 
artificially inoculated on oats {Avena saliva) . 
Also pathogenic on Agropyron repens. 

Source: Numerous isolations from 
blighted blades of oats. 

Habitat: Causes a halo spot on oats 
{Avena saliva). Artificial inoculations show 
barley (Hordeum vulgare), rye (Secale 
cereale) and wheat {Trilicum aesHvum) to be 
susceptible. 

70. Pseudotnonas lachrymans (Smith 
and Bryan, 1915) Carsner, 1918. {Bacterium 
lachrymans Smith and Bryan, Jour. Agr. 
Res., 5, 1915, 466; Carsner, Jour. Agr. Res., 
15, 1918, 201.) 

lach'ry.mans. L. lacrimo to shed tears; 
M.L. part. adj. lachrymans shedding tears. 



Description from Smith and Bryan {op. 
cit., 1915, 466) and Clara (Cornell Agr. Exp. 
Sta. Mem. 159, 1934,26). 

Rods 0.8 by 1.0 to 2.0 micron.s. Motile 
with 1 to 5 polar flagella. Encapsulated. 
Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Beef-peptone agar colonies: Circular, 
smooth, glistening, transparent, whitish, 
entire margins. 

Broth: Turbid in 24 hours. White precipi- 
tate with crystals. 

Milk: Turns alkaline and clears. 

Nitrites not produced from nitrates. 

Indole reaction weak. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, Phj-- 
topath.,5j?, 1942, 601). 

Acid but no gas from glucose, fructose, 
mannose, arabinose, xylose, sucrose and 
mannitol. Alkaline reaction from salts of 
citric, malic and succinic acids. Maltose, 
rhamnose, lactose, raffinose, glycerol and 
salicin not fermented (Clara, op. cil., 1934, 
26). 

Starch partially digested. Not digested 
(Clara, loc. cit.). 

Growth in 3 per cent salt after 12 days. No 
growth in 4 per cent salt. 

Temperature relations : Optimum between 
25° and 27° C. Minimum, 1° C. Maximum, 
35° C. 

Aerobic, facultative (Clara, loc. cit.). 

Source : Isolated from diseased cucumber 
leaves collected in New York, Wisconsin, 
Indiana and in Ontario, Canada. 

Habitat: Pathogenic on cucumber, Cucu- 
mis sativus, and related plants. 

71. Pseudomonas niaculicola (McCul- 
loch, 1911) Stevens, 1913. {Baclerium macu- 
licolum McCulloch, U. S. Dept. Agr., Bur. 
Plant Ind. Bui., 225, 1911, 14; Stevens, The 
Fungi which cause Plant Diseases, 1913, 28.) 

ma.cu.li'co.la. L. macula spot; L. -cola a 
dweller; M.L. noun maculicola spot dweller. 

Rods 0.9 by 1.5 to 3.0 microns. Filaments 
present. Motile with 1 to 5 polar flagella. 
Gram-negative. 



126 



ORDER I. PSEUDOMONADALES 



Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Beef -peptone agar colonies: Whitish, cir- 
cular, shining, translucent, edges entire. 

Broth: Turbid. No ring or pellicle. 

Milk: Becomes alkaline and clears. 

Nitrites not produced from nitrates. 

Indole production feeble. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 32, 1942, 601). 

Acid from glucose, galactose, xylose, su- 
crose, glycerol and mannitol. Alkaline reac- 
tion from salts of citric, malic, malonic and 
succinic acids. Salicin, maltose and salts of 
hippuric and tartaric acids not utilized 
(Burkholder). 

Slight growth in broth plus 4 per cent salt 
(Erw. Smith, Bact. Plant Diseases, 1920, 
306). 

Aerobic. 

Temperature relations : Optimum between 
24° and 25° C. Minimum, 0° C. Maximum, 
29° C. 

Source: Isolated from diseased cauliflower 
leaves from Virginia. 

Habitat: Pathogenic on cauliflower and 
cabbage. 

72. Pseudonionas mangiferaeindicae 

Patel et al., 1948. (Pseudonionas mangijerae- 
indicae (sic) Patel, Moniz and Kulkarni, 
Curr. Sci., 17, 1948, 189; Indian Phytopath., 
1, 1948, 147.) 

man.gi'fe.rae.in"di.cae. M.L. fem.noun 
Mangifera mango bearer; L. adj. indicus of 
Indm; mangiferaeindicae of Mangifera indica. 

Rods, 0.36 to 0.54 by 0.45 to 1.44 microns, 
occurring singly or in chains of 2 to 4. Motile 
with 1 or 2 polar flagella. Gram-negative. 

Gelatin: Liquefied. 

Nutrient agar colonies: Flat, smooth, 
glistening, round with entire margins, white 
to creamy, border deeper in color. 

Potato glucose agar slants: Growth 
copious, raised, smooth, glistening, filiform, 
opalescent, butyrous, white. 

Broth: Turbid with pellicle in 7 days. 
Slight sediment. 

Milk: Litmus reduced in 7 days. Cleared 
with gelatinous sediment. Casein digested. 

Loeffler's blood serum: Liquefied. 



Uschinsky's solution: Good growth. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

Acid but no gas from glucose, lactose and 
sucrose. Slight growth and acid in mannitol. 
L-arabinose, maltose, fructose, inulin, 
glycerol, salicin, sodium tartrate and 
asparagine not utilized. 

Starch hydrolyzed. 

Lipase not produced. 

Growth in 2 per cent salt. 

Temperature relations : Optimum between 
20° and 25° C. Minimum, 5° C. Maximum, 
35° C. 

Aerobic. 

Source: Isolated from diseased leaves of 
mangoes. 

Habitat : Pathogenic on Mangifera indica, 
Spondias mangiferae and Anacardium occi- 
dentale. 

73. Pseudonionas marginata (McCul- 

loch, 1921) Stapp, 1928. {Bacterium margi- 
natum McCulloch, Science, 54, 1921, 115; 
Jour. Agr. Res., 29, 1924, 174; Stapp, in 
Sorauer, Handbuch der Pflanzenkrank- 
heiten, 2, 5 Aufl., 1928, 56.) 

mar.gi.na'ta. L. margino to furnish with 
a border; L. part. adj. marginatus margined. 

Rods 0.5 to 0.6 by 0.8 to 1.8 microns. Mo- 
tile with 1 to 4 bipolar flagella. Encapsu- 
lated. Gram-negative. 

Green fluorescent pigment produced in 
Uschinsky's and Fermi's solutions. 

Gelatin: Liquefied. 

Agar colonies: White, circular, smooth, 
translucent, viscid, with definite margins at 
first thin but later thick and contoured. 
Surface wrinkled. 

Milk: At first slightly acid, then alkaline. 
Casein digested. 

Nitrites not produced from nitrates. 

Indole production slight. 

Hydrogen sulfide production slight. 

Lipolytic (Starr and Burkholder, Phyto- 
path., 32, 1942, 601). 

Acid but no gas from glucose, lactose, su- 
crose and glycerol. 

Starch hydrolysis feeble. 

Growth in 3.5 per cent salt. No growth in 
4 per cent salt. 

Temperature relations : Optimum between 



FAMILY IV. PSEUDOMONADACEAE 



127 



30° and 32° C. Minimum between 8° and 
9° C. Maximum, 40° C. 

pH range, 4.6 to 9.1. 

Source : Repeatedly isolated from diseased 
gladiolus. 

Habitat: Pathogenic onGladiolus spp. and 
7m spp. 

74. Pseudonionas inedicaginis Sackett, 
1910. (Science, 31, 1910, 553; also Colorado 
Agr. Exp. Sta., Bull. 158, 1910, 11.) 

me.di.ca'gi.nis. Gr. medice the Median 
grass, alfalfa, lucerne, medic; M.L. fern, 
noun Medicago generic name of alfalfa; M.L. 
fem. gen. noun medicaginis of lucerne or 
alfalfa. 

Rods 0.7 by 1.2 microns. Motile with 1 to 
4 flagella. Filaments present. Gram-nega- 
tive. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Not liquefied. 

Nutrient agar colonies: Growth in 24 
hours whitish, glistening. 

Broth: Turbid in 24 hours. Pellicle 
formed. Viscid sediment. 

Milk: Becomes alkaline. No change. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 3£, 1942, 601). 

Starch not hydrolyzed. 

No gas from carbohydrates. Acid from 
sucrose. 

Slight growth in broth plus 3.75 per cent 
salt. 

Temperature relations : Optimum between 
28° and 30° C. Maximum, 37.5°C. 

Aerobic. 

Source: Isolated from brown lesions on 
leaves and stems of alfalfa. 

Habitat: Pathogenic on alfalfa, Medicago 
sp. 

75. Pseudomonas phaseolicola (Burk- 
holder, 1926) Dowson, 1943. (Phytomonas 
medicaginis var. phaseolicola Burkholder, 
Phytopath., 16, 1926, 915; Dowson, Trans. 
Brit. Mycol. Soc, 26, 1943, 10.) 

pha.se.o.li'co.la. Gr. phaseolus the kid- 
ney bean; L. dim. mas. noun phaseolus the 
kidney bean; L.mas.gen.noun phaseoli of the 



bean; L. cola dweller; M.L. fem. noun 
phaseolicola the bean dweller. 

Description from Burkholder and Zaleski 
(Phytopath., ^^, 1932, 85). 

Rods 1.0 by 2.0 microns, sometimes 
slightly curved; filaments present. Motile 
with a polar flagellum. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin stab: Slow liquefaction. 

Beef extract agar: Whitish, circular 
colonies, 2 mm in diameter. Edges entire. 

Broth: Turbid. 

Milk: Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 82, 1942, 601). 

Acid but no gas from glucose, fructose, 
mannose, arabinose, xylose, sucrose and 
glycerol. No acid from rhamnose, lactose, 
maltose, mannitol or salicin. Alkali from 
salts of citric and malic acids, but not from 
acetic, formic, lactic or tartaric acids. 
Starch and cellulose not hydrolyzed. 

Slight growth in broth plus 4 per cent salt. 

Temperature relations : Optimum between 
20° and 23° C. Minimum, 2.5° C. Maximum, 
33° C. (Hedges, Jour. Agr. Res., 36, 1928, 
428). 

Chemical tolerance: Optimum pH be- 
tween 6.7 and 7.3. Minimum between 5.0 
and 5.3. Maximum between 8.8 and 9.2 
(Kotte, Phyt. Zeitsch., 2, 1930 453). 

Microaerophilic. 

Source: Isolated from leaves, pod and 
stem of beans showing halo blight. 

Habitat: Pathogenic on beans (Phaseo- 
lus vidgaris), the kudzu vine (Pueraria 
hirsuta) and related plants. 

76. Pseudonionas pisi Sackett, 1916. 
(Colorado Agr. Exp. Sta., Bull. 218, 1916, 
19.) 

pi'si. Gr. pisus or pisum the pea; M.L. 
neut.noun Pisum generic name of the pea; 
M.L. neut. gen. noun pisi of the pea. 

Rods 0.68 to 2.26 microns. Motile with a 
polar flagellum. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 



128 



ORDER I. PSEUDOMONADALES 



Agar slants : Moderate growth in 24 hours, 
filiform, glistening, grayish white. 

Broth: Turbid with a scum in 5 days. 

Milk: Alkaline, soft curd, clears. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hj'drogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 32, 1942, 601). 

Acid but no gas from glucose, galactose 
and sucrose. 

Starch not hydrolyzed. 

Temperature relations : Optimum between 
27° and 28° C. Minimum, 7° C. Maximum, 
37.5° C. 

Aerobic. 

Source: Ten cultures isolated from 5 col- 
lections of diseased peas showing water- 
soaked lesions on stems and petioles. 

Habitat: Pathogenic on garden peas, 
Pisum sativum, and field peas, P. sativum 
var. arvense. 

77. Pseudonionas syringae van Hall, 
1902. (Kennis der Bakt. Pflanzenziekte, 
Inaug. Diss., Amsterdam, 1902, 191.) 

sy.rin'gae. Gr. syrinx, syringis a pipe or 
tube; M.L. fem.noun Syringa generic name 
of syringa or lilac; M.L. fem. gen. noun. 
syringae of the lilac. 

Description from Clara (Cornell Agr. 
Exp. Sta. Mem. 159, 1934, 29). 

Rods 0.75 to 1.5 by 1.5 to 3.0 microns. 
Motile with 1 or 2 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Beef -extract agar colonies: Circular, 
grayish white with bluish tinge. Surface 
smooth. Edges entire or irregular. 

Broth: Turbid in 36 hours. No pellicle. 

Milk: Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 3^, 1942, 601). 

Slight growth in broth plus 4 per cent salt. 

Acid but no gas from glucose, galactose, 
mannose, arabinose, xylose, sucrose, man- 
nitol and glycerol. Alkaline reaction from 
salts of citric, malic, succinic and lactic 



acids. Rhamnose, maltose, lactose, raffinose, 
salicin, and acetic, formic and tartaric acids 
not fermented. 

Starch not hydrolj'zed. 

Aerobic, facultative. 

Comment: Orsini (Intern. Bull. Plant 
Protect., S3, 1942, 33) reports that a variety 
of this species is pathogenic on the pepper 
plant {Capsicum). 

Source: Van Hall originally isolated this 
pathogen from lilac. 

Habitat: Pathogenic on lilac, citrus, cow 
peas, beans, lemons, cherries and many un- 
related plants. 

78. Pseudonionas tomato (Okabe, 1933) 
Alstatt, 1944. {Bacterium tomato Okabe, 
Jour. Soc. Trop. Agr. Formosa, 5, 1933, 32; .„ 
Alstatt, U. S. Dept. Agr., Plant Dis. Rept., 
28, 1944, 530.) 

to.ma'to. Am.Ind. tomatl; Sp. tornate; 
Eng. tomato; M.L. noun tomato. 

Rods 0.69 to 0.97 by 1.8 to 6.8 microns. 
Motile with 1 to 3 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Slow liquefaction. 

Beef -extract agar colonies: White, circu- 
lar, flat and glistening. 

Broth: Turbid in 24 hours. Pellicle. 

Milk: Becomes alkaline and clears. 

Nitrites are usually produced from ni- 
trates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, sucrose and 
lactose. No acid from maltose or glycerol. 

Starch hydrolysis feeble. 

Slight growth in 3 per cent salt. 

Temperature relations : Optimum between 
20° and 25° C. Maximum, 33° C. 

Aerobic. 

Source: Isolated from diseased tomato 
leaves. 

Habitat: Pathogenic on tomato, Lyco- 
persicon esculenium. 

79. Pseudomonas atrofaciens (McCul- 
loch, 1920) Stevens, 1925. {Bacterium atro- 
faciens McCulloch, Jour. Agr. Res., 18, 1920, 
549; Stevens, Plant Disease Fungi, New 
York, 1925, 22.) 



FAMILY IV. PSEUDOMONADACEAE 



129 



at.ro.fa'ci.ens. L. ater black; L. facio to 
make;M.L. part. adj. atrofaciens blackening. 

Rods 0.6 by 1.0 to 2.7 microns. Long 
chains formed in culture. Encapsulated. 
Motile with 1 to 4 polar or bipolar flagella. 
Gram-negative 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Beef-peptone-agar colonies: Circular, 
shining, translucent, white. 

Broth: Growth never heavy, slight rim, 
and a delicate pellicle. 

Milk: Becomes alkaline and clears. 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Indole: Slight production. 

Hydrogen sulfide: Slight production. 

Acid but no gas from glucose, galactose 
and sucrose. 

Starch is slightly hydrolyzed. 

Temperature relations : Optimum between 
25° and 28° C. Minimum below 2° C. Maxi- 
mum between 36° and 37° C. 

Aerobic. 

Source: Isolated from diseased wheat 
grains collected throughout the United 
States and Canada. 

Habitat: Causes a basal glume-rot of 
wheat. 

80. Pseudomonas cuniini (Kovachev- 
ski, 1936) Dowson, 1943. {Phytomonas cumini 
Kovachevski, Bull. Soc. Bot. Bulgarie, 7, 
1936, 27; Dowson, Trans. Brit. Mycol. Soc, 
m, 1943, 10.) 

cu'mi.ni. Gr. cuminum cumin; M.L. 
neut.noun Cuminum generic name of cu- 
min; M.L. neut. gen. noun cumini of cumin. 

Rods, 0.5 to 0.7 by 1.0 to 3.0 microns, oc- 
curring in chains and filaments. Motile with 
1 to 3 polar fiagella. Gram-negative. 

Green fluorescent pigment formed in cul- 
ture. 

Gelatin: Rapidly liquefied. 

Potato agar colonies: Grayish white, cir- 
cular, glistening, smooth, butyrous. 

Broth: Moderate turbidity. Pseudozoo- 
gloea. 

Milk: Not coagulated. Casein peptonized. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 



Acid but no gas from glucose and sucrose. 
No acid from lactose or glycerol. Starch not 
hydrolyzed. 

Temperature range, 5° to 31° C. 

Aerobic. 

Source: Isolated from blighted cumin 
(Cuminian). 

Habitat: Pathogenic on cumin and dill. 

81. Pseudomonas desaiana (Burk- 
holder, 1939) Savulescu, 1947. (B. pyo- 
cyaneiis saccharum Desai, Ind. Jour. Agr. 
Sci., 5, 1935, 391; Phytomonas desaiana Burk- 
holder, in Bergey et al., Manual, 5th ed., 
1939, 174; Savulescu, Anal. Acad. Romane, 
III, 22, 1947 11.) 

de.sai.a'na. M.L. adj. desaianus. Named 
for Prof. Desai of India. 

Rods 0.6 to 1.2 by 1.2 to 2.2 microns. Mo- 
tile with a polar flagellum. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Agar colonies: Grayish blue. Raised. 

Broth: Light clouding. Pellicle. 

Milk: Peptonized without coagulation. 

Nitrites not produced from nitrates. 

Indole not produced. 

Glucose, sucrose, lactose and gh'cerol fer- 
mented without gas. 

Starch: Hydrolysis present. 

Optimum temperature, 30° C. 

Aerobic. 

Source: Isolated from stinking rot of 
sugar cane in India and associated with a 
white non-pathogenic bacterium. 

Habitat: Pathogenic on sugar cane, Sac- 
char u m officinaru tn . 

82. Pseudomonas erodii Lewis, 1914. 
(Phytopath.,.^, 1914,231.) 

e.ro'di.i. Gr. erodius the heron; M.L. 
neut.noun Erodium generic name of heron- 
bill; M.L. neut. gen. noun erodii of Erodium. 

Rods 0.6 to 0.8 by 1.2 to 1.8 microns. 
Motile with 1 to 3 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Agar streak: Heavy, smooth, cream- 
colored growth in 24 hours. 

Broth: Dense clouding in 24 hours. 



130 



ORDER I. PSEUDOMONADALES 



Milk: Turns alkaline and clears, litmus 
reduced. 

Nitrites not produced from nitrates. 

Indole produced in 14 days. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, sucrose, lac- 
tose and glycerol. 

Temperature: No growth at 35° C. 

Aerobic, obligate. 

Source: Isolated from Erodium texanum 
and 4 varieties of Pelargonium. 

Habitat: Causes a leaf spot of Erodium 
texanum and Pelargonium spp. 

83. Pseudomonas lapsa (Ark, 1940) 
Starr and Burkholder, 1942. {Phytomonas 
lapsa Ark, Phytopath., 30, 1940, 1 ; Starr and 
Burkholder, Phytopath., SS, 1942, 601.) 

lap'sa. L. V. labor to fall down, slip; L. 
part. adj. lapsus fallen down. 

Rods 0.56 by 1.55 microns. Motile, with 
1 to 4 polar flagella. Gram reaction not re- 
ported; presumably Gram-negative. 

Produces fluorescence in Uschinsky's, 
Fermi's and Cohn's solutions. 

Gelatin: Liquefied (Burkholder). 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Acid but no gas from glucose, sucrose, 
maltose, lactose, glycerol, arabinose, xy- 
lose, galactose, raffinose and mannitol. 

Slight grow^th in broth plus 5 per cent salt 
(Burkholder). 

Relationship to other species: Resembles 
Pseudomonas desaiana. 

Source: Isolated from stalk rot of field 
corn in California; also from Diabrotica 
beetles. 

Habitat: Pathogenic on corn and sugar 
cane. 

84. Pseudomonas martyniae (Elliott, 
1924) Stapp, 1928. {Bacterium martyniae 
Elliott, Jour. Agr. Res., 29, 1924, 490; Stapp, 
in Sorauer, Handbuch der Pflanzenkrank- 
heiten,^, 5 Aufl., 1928,278.) 

mar.tyn'i.ae. M.L. Martynia genus of 
flowering plants; M.L. gen.fem. martyniae of 
Martynia. 

Rods, 0.59 to 1.68 microns, occurring in 
chains. Encapsulated. Motile with one to 
several bipolar flagella. Gram-negative. 

Green fluorescent pigment produced. 



Gelatin: Liquefied. 

Beef agar colonies: White, round, smooth, 
glistening, raised. 

Broth: Clouding in bands. Thin pellicle. 
Small crystals. 

Milk: Soft acid curd with peptonization. 

Nitrites jiroduced from nitrates after 2 
weeks. 

Indole not produced. 

Hydrogen sulfide production slight. 

Acid but no gas from glucose, galactose, 
arabinose and sucrose. No acid from rham- 
nose, lactose, maltose, raffinose, mannitol 
or glycerol. 

Starch hydrolysis none or feeble. 

Temperature relations: Optimum, 26° C. 
Minimum, 1.5° C. Maximum, 37° C. 

Chemical tolerance: Optimum pH, 6.0 to 
6.7. pH range, 5.4 to 8.9. 

Aerobic. 

Source: Isolated from diseased leaves of 
the unicorn plant from Kansas. 

Habitat: Pathogenic on Martynia louisi- 
ana. 

85. Pseudomonas matthiolae (Briosi and 
Pavarino, 1912) Dowson, 1943. {Bacterium 
matthiolae Briosi and Pavarino, Atti della 
Reale Accad. dei Lincei Rend.,^i, 1912, 216; 
Dowson, Trans. Brit. Mycol. Soc, 26, 1943, 
10.) 

mat.thi'o.lae. Mattioli patronymic; M.L. 
fern. noun Matthiola generic name of stock; 
M.L. fern. gen. noun matthiolae of Matthiola. 

Rods 0.4 to 0.6 by 2.0 to 4.0 microns. 
Gram-positive. Gram-negative (Mushin, 
Proc. Roy. Soc. Victoria, 53, 1941, 201). 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Beef agar colonies: White, circular, 
slightly elevated, margins smooth. 

Broth: Slightly turbid. Becomes pale 
green. 

Milk: Coagulation with acid reaction. 

Nitrites produced from nitrates (Mushin, 
Proc. Trans. Brit. Mycol. Soc, 26, 1943, 10). 

Hydrogen sulfide not produced. 

Acid from glucose, galactose, fructose, 
mannose, rhamnose, glycerol, mannitol, 
acetic acid, citric acid, formic acid, lactic 
acid, malic acid and succinic acid. Feeble 
acid from maltose. No acid or gas from lac- 



FAMILY IV. PSEUDOMONADACEAE 



131 



tose, sucrose, raffinose, starch, salicin or 
tartaric acid (Mushin). 

Temperature relations : Optimum, between 
20° and 24° C. Minimum, below 0° C. Maxi- 
mum, 38.5° C. (Mushin). 

Limits of growth in broth are pH 4.4 to 
pH 9.5 (Mushin). 

Aerobic. 

Source: Isolated from vascular and 
parenchymatic disease of stocks, Matthiola 
incana var. annua. 

Habitat: Pathogenic on stocks. 

86. Pseudonionas inorsprunoruin Wor- 

mald, 1931. {Pseudomonas mors-pnmorum 
(sic) Wormald, Jour. Pom. and Hort. Sci., 
9, 1931, 251.) 

mors'pru.no.rum. L. mors death; L. 
prunus plum; M.L. fem.noun morspruno- 
rum plum death. 

Rods. Motile with a polar flagellum. 
Gram-positive (1931). Gram-negative 
(1932). 

Gelatin: Liquefied. 

Agar colonies: White. 

Broth plus 5 per cent sucrose : White and 
cloudy. 

Nitrites not produced from nitrates. 

Acid but no gas from glucose, lactose, 
sucrose and glycerol. 

Starch not hydrolyzed. 

Strict aerobe. 

Comment: Possibly a green fluorescent 
organism since it produces a faint yellow 
color in Uschinsky's solution. 

Distinctive characters: Differs from 
Pseudomonas prunicola (Pseudomonas syrin- 
gae) in that it produces a white cloudy 
growth in broth plus 5 per cent sucrose, a 
rapid acid production in nutrient agar plus 
5 per cent sucrose, and a faint yellow or no 
color in Uschinsky's solution. 

Source: Isolated from cankers on plum 
trees in England. 

Habitat: Pathogenic on Prunus spp. 

87. Pseudomonas papulans Rose, 1917. 
(Phytopath., 7, 1917, 198.) 

pa'pu.lans. L. v. papulo to produce pus- 
tules; L. part. adj. papulans producing 
pustules. 

Rods 0.8 by 0.8 to 2.5 microns. Motile 
with 1 to 6 polar flagella. Gram-negative. 



Green, fluorescent pigment produced in 
various media. 

Gelatin: Liquefied. 

Broth: Turbid with pellicle. 

Fermi's and Uschinsky's solutions: Good 
growth. 

Milk: Litmus reduced; no acid. 

Nitrites not produced from nitrates. Ni- 
trites produced from nitrates (Burkholder 
and Starr, Phytopath., 38, 1948, 498). 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, fructose, 
galactose, mannose, arabinose, xylose, su- 
crose, glycerol, mannitol, sorbitol, salicin 
and esculin. 

No acid or gas from rhamnose, lactose, 
maltose, raffinose, trehalose, melizitose, 
starch, inulin, dextrin, dulcitol or arbutin. 

Alkaline reaction produced in glycogen 
and in acetic, citric, formic, lactic, malic 
and succinic acids. 

Temperature relations: Optimum, 27° C. 
Minimum, 3.5° C. Maximum, 34.5° C. 

Chemical tolerance: Optimum pH, 7.0. 
Minimum, 5.0. Maximum, 9.4. 

Source: Twenty-five cultures isolated 
from blisters on apples and from rough bark. 

Habitat: Pathogenic on apple trees. 

88. Pseudomoiias pseudozoogloeae 

(Honing, 1914) Stapp, 1928. (Bacterium 
pseudozoogloeae Honing, Bull, van Het. Deli 
Proefstation, Medan, 1, 1914, 7; Stapp, in 
Sorauer, Handbuch der Pflanzenkrank- 
heiten, ^, 5 Aufl., 1928,274.) 

pseu.do.zo.o.gloe'ae. Gr. pseudes false; 
Gr. zoum animal; Gr. gloea glue; M.L. 
fem.noun Zoogloea bacterial generic name; 
M.L. fem. gen. noun pseudozoogloeae of a 
false zoogloea. 

Rods 0.7 to 1.5 by 0.9 to 2.5 microns. 
Chains. Motile with 1 or 2 polar flagella. 
Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Agar colonies: Round, flat, yellow-gray. 

Broth: Moderate turbidity with pseudo- 
zoogloeae in the pellicle. 

Milk: Coagulation. No clearing. 

Nitrites not produced from nitrates. 

Indole not produced. 



132 



ORDER I. PSEUDOMONADALES 



Hydrogen sulfide produced. 

Acid but no gas from glucose, lactose, mal- 
tose, sucrose and mannitol. 

Aerobic, facultative. 

Source: Isolated from the black rust of 
tobacco. 

Habitat: Pathogenic on tobacco, Nico- 
tiana tnbacum. 

89. Pseudomoiia.s riniaefaciens Koning, 
1938. (Chron. Bot., 4, 1938, 11; Meded. 
Phj-top. Labor, Willie Comm. Scholt., 14, 
1938, 24.) 

ri.mae.fa'ci.ens. L. rima a crack; L. v. 
facio to make; M.L. part. adj. riniaefaciens 
making cracks. 

Rods 0.6 to 2.4 microns in length. Motile 
with 1 to 3 flagella. Gram-negative. 

Yellow-green, fluorescent, water-soluble 
pigment produced in culture. 

Gelatin: Liquefied. 

Agar colonies: Round, conve.x, smooth, 
somewhat granular with hyaline edge. 

Broth: Turbid. Surface growth with a 
sediment in a few days. 

Milk: Alkaline and clears. 

Nitrites not produced from nitrates. Pep- 
tone, asparagin, urea, gelatin, nitrates and 
ammonium salts are sources of nitrogen. 

Hydrogen sulfide not produced. 

Indole production slight. 

Growth with the following carbon sources 
plus NO3 : glucose, sucrose, glycerol, suc- 
cinates, malates, citrates and oxalates. Less 
growth with mannitol, fructose, galactose, 
lactose and salicylate. Acid is produced 
from the sugars. No growth with dextrin, 
inulin, maltose, lactose, rhamnose, salicin, 
tartrates, acetates or formates. 

Starch not hydrolyzed. 

Aerobic. 

Temperature relations: Optimum, 25° C. 
Very slow growth at 14° C. Maximum, about 
37° C. Thermal death point between 42° and 
48° C. 

Relationship to other species: This may 
be Pseudomonas syringae since the charac- 
ters are the same and both organisms can 
infect Impatiens sp. Pseudomonas syringae 
infects poplars (Elliott, Bacterial Plant 
Pathogens, 1930, 218). 

Source: Strains of the pathogen isolated 



from poplar cankers in France and in the 
Netherlands. 

Habitat: Pathogenic on Populus braban- 
tica, P. trichocarpa and P. candicans. 

90. Pseudomonas striafaciens (Elliott, 
1927) Starr and Burkholder, 1942. (Bac- y 
terium striafaciens Elliott, Jour. Agr. Res., 
35, 1927, 823; Starr and Burkholder, Phyto- 
path., 32, 1942, 601.) 

stri.a.fa'ci.ens. L. stria a furrow; M.L. 
part. adj. striafaciens furrowing. 

Rods 0.66 by 1.76 microns. Motile with 
one to several flagella. Encapsulated. Gram- 
negative. 

Green fluorescent pigment produced. 

Gelatin: Liquefied. 

Beef -peptone agar colonies: White, 
raised, margins entire or slighth' undulat- 
ing. 

Broth: Clouding in layers. Ring and slight 
pellicle. 

Milk: Alkaline, sometimes a soft curd 
w^hich digests or clears. 

Slight production of nitrites from ni- 
trates. 

Indole not produced. 

Acid but no gas from glucose, fructose 
and sucrose. No acid from lactose, maltose, 
glycerol or mannitol. 

Starch: Hydrolysis slight. 

Optimum temperature, 22° C. 

Optimum pH, between 6.5 and 7.0. 

Aerobic. 

Distinctive characters: Differs from 
Pseudomonas coronafaciens in that the cells 
are somewhat smaller and the pathogen pro- 
duces a streak on oat blades instead of a 
halo spot. 

Source : Forty cultures isolated from oats 
gathered in various parts of America. 

Habitat: Pathogenic on cultivated oats 
and, to a slight degree, on barley. 

91. Pseudomonas tabaci (Wolf and 
Foster, 1917) Stevens, 1925. {Bacterium ta- 
bacum (sic) Wolf and Foster, Science, 46, 
1917, 362; also Jour. Agr. Res., 12, 1918, 449; 
Stevens, Plant Disease Fungi, New York, 
1925, 36.) 

ta.ba'ci. M.L. noun iabacum tobacco; 
M.L. gen. noun tabaci of tobacco. 



FAMILY IV. PSEUDOMONADACEAE 



133 



Rods 1.2 by 3.3 microns. Motile with a 
polar flagellum. Gram-negative. 

Gelatin: Liquefied. 

Potato agar colonies: Grayish white, cir- 
cular, raised, wet-shining, smooth. 

Milk: Alkaline; clears. 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Indole not produced. 

Acid from glucose, galactose, fructose, 
1-arabinose, xj'lose, sucrose, pectin, man- 
nitol and glycerol (Braun, Phytopath., 27, 
1937, 289). 

Ammonium sulfate, potassium nitrate, 
cystine, glutamic acid, glycine, succin- 
imide, oxamide, acetamide and urea can be 
used as nitrogen sources (Braun). 

Starch not hydrolyzed. 

Aerobic. 

Relationship to other species: Braun {loc. 
cit.) states that Pseudomonas tabaci and 
Pseiidomonas angulata are identical in 
culture. 

Source: Isolated from wildfire lesions and 
tobacco leaves in North Carolina. 

Habitat: Pathogenic on tobacco, Nico- 
tinna fabacvm. 

92. Pseudoniona.s poly color Clara, 1930. 
(Phytopath., 20, 1930, 704.) 

po.lj^'co.lor. Gr. poly- many; L. color 
color; M.L. adj. polycolor many colored. 

Description taken from Clara (Cornell 
Agr. E.xp. Sta. Mem. 159, 1934, 28). 

Rods 0.75 to 1.2 by 1.05 to 3.0 microns. 
Motile with 1 or 2 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Beef -extract agar colonies: Graj^ish 
white, circular, raised; thin, transparent 
margins. 

Broth: Turbid in 36 hours with thin pel- 
licle. 

Milk: Alkaline; no curd. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Lipolytic (Starr and Burkholder, Phyto- 
path., 32, 1942, 601). 

Acid l)Ut no gas from glucose, galactose. 



fructose, mannose, arabino.se, xylose, man- 
nitol and glycerol. Alkaline reaction from 
salts of acetic, citric, malic, lactic and for- 
mic acids. Rhamnose, sucrose, maltose, lac- 
tose, raffinose and salicin not fermented. 

Starch not hydrolyzed. 

Aerobic, facultative. 

Good growth in broth plus 7 per cent salt. 

Temperature relations: Optimum be- 
tween 25° and 30° C. Maximum between 37° 
and 39° C. 

Distinctive characters: Differs from 
Pseudomonas mellea in type of lesion pro- 
duced; does not digest starch nor reduce 
nitrates and does not form acid from lactose 
nor sucrose. Pathogenic for laboratory ani- 
mals (Elrod and Braun, Sci., 94, 1941, 520). 
Cultural characters differ from those of 
Pseudomonas aeruginosa Migula. 

Source: Repeatedly isolated from leaf 
spot of tobacco in the Philippines. 

Habitat: Pathogenic on tobacco. 

93. Pseudomonas viridiflava (Burk- 
holder, 1930) Clara, 1934. (Phytomonas viri- 
diflava Burkholder, Cornell Agr. Exp. Sta. 
Mem. 127, 1930, 63; Clara, Science, 75, 1934, 
111.) 

vi.ri.di.fla'va. L. viridis green; L. flavus 
yellow; M.L. adj. viridiflavus greenish 
yellow. 

Description from Clara (Cornell Agr. 
Exp. Sta. Mem. 139, 1934, 30). 

Rods 0.75 to 1.5 by 1.5 to 3.15 microns. 
Motile with 1 or 2 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Beef -extract agar colonies: Grayish 
white, margins corrugated, edges irregular. 

Broth: Turbid in 36 hours. 

Milk: Becomes alkaline and clears. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath.,3^, 1942, 601). 

Acid but no gas from glucose, fructose, 
mannose, arabinose, xjdose, mannitol and 
glycerol. Alkaline reaction from salts of 
acetic, citric, malic, lactic and succinic 



134 



ORDER I. PSEUDOMONADALES 



acids. Sucrose, lactose, maltose, raffinose, 
salicin, and salts of formic and tartaric acids 
not fermented. 

Starch: No hydrolj'sis. 

Growth in broth plus 5 per cent NaCl. 

Aerobic, facultative. 

Comment: A variety that does not grow 
in Uschinsky's solution and that produces 
colonies of an unusual shape has been iso- 
lated from the stems and leaves of blighted 
beans in Denmark. See Petersen (Tidsskr. 
f. Planteavl., 38, 1932, 851). 

Source: Two cultures isolated from 
spotted beans, one from England and one 
from Switzerland. 

Habitat: Pathogenic on bean, Phaseolus 
vulgaris. 

94. Pseudoitionas ananas Serrano, 1934. 
(Philipp. Jour. Sci., 55, 1934, 355.) 

a'na.nas. Braz.Ind. ananas pineapple; 
M.L. indecl.neut.noun ananas. 

Rods 0.6 by 1.8 microns. Motile with 1 to 
4 polar flagella. Gram-negative. 

Green fluorescent pigment produced in 
certain media. 

Gelatin: Liquefied. 

Beef -extract glucose agar colonies: White, 
with undulating edges, smooth to rugose, 
glistening to dull. 

Beef-extract agar: Growth scant. 

Broth: Feeble growth. 

Milk: Becomes alkaline with curd. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, xylose and 
mannitol. Feeble with lactose. No acid from 
sucrose. 

Starch not hydrolyzed. 

Temperature relations : Optimum between 
30° and 31° C. Minimum between 7° and 
10° C. Maximum, 45° C. 

Aerobic. 

Source: Isolated from rotted pineapples. 

Habitat: Causes a rot of pineapples. 
Ananas comosus. 

95. Pseudomonas bowlesiae (Lewis and 



Watson, 1927) Dowson, 1943.* (Phytomonas 
bowlesii (sic) Lewis and Watson, Phyto- 
path., 17, 1927, 511; Pseudomonas bowlesiae 
Dowson, Trans. Brit. Mycol. Soc, 26, 1943, 
9.) 

bow.le'si.ae. M.L. fem.n. Bowlesia ge- 
neric name; M.L. gen. noun bowlesiae of 
Bowlesia. 

Rods, 0.5 to 0.7 by 1.2 to 1.6 microns, 
occurring singly, in pairs or in short chains. 
Motile with bipolar flagella. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Agar slants: Yellowish, moist, glistening 
and viscid. 

Broth: Uniform turbidity throughout. 
Heavy viscous sediment in old cultures. 

Milk: Alkaline; coagulation with a slow 
peptonization. 

Nitrites produced from nitrates. 

Indole produced. 

Hj'drogen sulfide produced. 

Acid from glucose, maltose and xylose. 
No acid from sucrose. 

Temperature relations: Optimum, 27° C. 
Minimum, —1° C. Maximum, 37° C. 

Chemical tolerance: Optimum pH, 7.2. 
pH range, 4.5 to 8.6. 

Aerobic. 

Source: Isolated from diseased, water- 
soaked spots of bowlesia. 

Habitat: Pathogenic on Bowlesia septen- 
trionalis. 

96. Pseudomonas ligustri (d'Oliveira, 
1936) SSvulescu, 1947. {Bacterium ligustri 
d'Oliveira, Revista Agron., 2J^, 1936, 434; 
Savulescu, Anal. Acad. Romane, III, 22, 
1947, 11.) 

li.gus'tri. L. ligustrum the privet; M.L. 
neut.noun Ligustrum generic name of 
privet; ligustri of the privet. 

Rods 0.5 to 0.7 by 1.3 to 3.0 microns. No 
chains. Not encapsulated. Motile with 2 to 
5 polar flagella. Gram-negative. 

Green pigment produced on Dox agar and 
in broth. 

Gelatin: Liquefied. 



* The authors of this binomial report (personal communication) that the original spell- 
ing bowlesii used for the specific epithet is an orthographic error. The correct spelling is 
"bowlesiae" . 



FAMILY IV. PSEUDOMONADACEAE 



135 



Beef -extract agar colonies: Growth mod- 
erate. Milky white, circular, convex. 

Broth: Turbid in 24 hours. No pellicle. 

Milk: Coagulated in 6 days and later di- 
gested. Litmus slightly acid. 

Nitrites not produced from nitrates. 

Indole not produced. 

Ammonia not produced. 

No gas from carbohydrates. Acid from 
glucose, galactose, arabinose and mannose. 
No acid from sucrose, maltose, lactose, raf- 
finose, raannitol or salicin. 

Source: From diseased Japanese privet 
in Lisbon, Portugal. 

Habitat: Pathogenic on privet, Ligus- 
trum ja'ponicum. 

97. Pseudomonas marginalis (Brown, 
1918) Stevens, 1925. {Bacterium marginale 
Brown, Jour. Agr. Res., 13, 1918, 386; 
Stevens, Plant Disease Fungi, New York, 
1925, 30; Phyfomonas intyhi Swingle, Phyto- 
path., 15, 1925, 730.) 

mar.gi.na'lis. L. margo, marginis edge, 
margin; M.L. adj. marginalis marginal. 

Description from Brown (op. cit., 1918, 
386) and Clara (Cornell Agr. Exp. Sta. Mem. 
159, 1934, 27). 

Rods. Motile with 1 to 3 polar flagella. 
Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Agar colonies: Cream-colored to yellow- 
ish. 

Broth: Turbid, with pellicle. 

Milk: Alkaline. Soft curd at times. 

Nitrites are produced from nitrates. Not 
produced (Clara). 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, galactose, 
fructose, mannose, arabinose, xylose, rham- 
nose, mannitol and glycerol. Alkali from 
salts of acetic, citric, malic, formic, lactic, 
succinic and tartaric acids. Sucrose, mal- 
tose, lactose, raffinose and salicin not fer- 
mented (Clara). 

Starch hydrolysis feeble. None (Clara). 

Temperature relations : Optimum between 
25° and 26° C. Minimum, 0° C. Maximum, 
38° C. 

Aerobic. 



Source: Isolated from marginal lesion on 
lettuce from Kansas. 

Habitat: Pathogenic on lettuce and re- 
lated plants. 

98. Pseudomonas sesami Malkoff, 1906. 
(Cent. f. Bakt., II Abt., 16, 1906, 665.) 

se'sa.mi. Gr. sesamum sesame; M.L. 
neut.noun Sesamum generic name of sesame; 
sesami of sesame. 

Description from Nakata (Ann. Phyt. 
Soc. Japan, .?, 1930, 242). 

Rods 0.6 to 0.8 by 1.2 to 3.8 microns. 
Motile with 2 to 5 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefaction rapid. 

Beef -agar colonies: Circular, flat, striate, 
smooth, entire margins, white. 

Broth: Growth rapid. No pellicle. 

Milk: Alkaline. No coagulation. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose. No acid 
from lactose, sucrose or glycerol. 

Starch not hj^drolyzed. 

Temperature relations: Optimum, 30° C. 
Minimum, 0° C. Maximum, 35° C. 

Aerobic, facultative. 

Source: Isolated from l)rown spots on 
leaves and stems of sesame. 

Habitat: Pathogenic on sesame. 

99. Pseudomonas setariae (Okabe, 
1934) Savulescu, 1947. (Bacterium setariae 
Okabe, Jour. Soc. Trop. Agr. Formosa, 6, 
1934, 63; SSvulescu, Anal. Acad. Romane, 
III, 22, 1947, 11.) 

se.ta'ri.ae. L. saeta a bristle; M.L. 
saetarius bristle-like; M.L. fem.noun Se- 
taria generic name of foxtail; setariae of 
Setaria. 

Rods 0.4 to 0.8 by 1.8 to 4.4 microns. 
Motile with a polar, seldom bipolar, flagel- 
lum. Gram-negative. 

Yellowish, water-soluble pigment pro- 
duced in culture. 

Gelatin: Slow liquefaction. 

Beef -extract agar colonies: Circular, 
white, opalescent, smooth, glistening. 

Broth: Tur])id after 18 hours. Pellicle. 



136 



ORDER I. PSEUDOMONADALES 



Milk: Alkaline; clears. 

Nitrites produced from nitrates. 

Indole produced. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, galactose 
and glycerol. No acid from lactose, maltose 
or sucrose. 

Starch: Feeble hydrolysis. 

Grows in 3 per cent salt. 

Temperature relations: Optimum be- 
tween 31° and 34° C. Maximum, 42° C. 

Aerobic. 

Source: Isolated from brown stripe of 
Italian millet. 

Habitat: Pathogenic on Italian millet, 
Setaria italica. 

100. Pseudomonas tolaasii Paine, 1919. 
(Ann. Appl. Biol., 5, 1919, 210.) 

to.laa'si.i. Tolaas patronymic; tolaasii 
of Tolaas. 

Rods 0.4 to 0.5 by 0.9 to 1.7 microns. 
Motile with 1 to 5 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Bouillon agar: Streak develops in 24 
hours, dirty bluish white, wet-shining and 
slightly raised. 

Broth: Turbid in 24 hours. Pellicle. 

Milk: Becomes alkaline and clears. 

Nitrites not produced from nitrates. 

Indole production slight. 

Acid but no gas from glucose. No acid 
from lactose or sucrose. 

Starch hydrolysis feeble. 

Optimum temperature, 25° C. 

Source : Isolated in England from brown- 
spot of cultivated mushrooms. 

Habitat: Pathogenic on cultivated mush- 



101. Pseudomonas washingtoiiiae 

(Pine 1943) Elliott 1951. {Phytomonas 
washingtoniae Pine, Phytopath., 33, 1943, 
1203; Elliott, Man. Bact. Plant Path., 2nd 
ed., 1951, 100.) 

wash.ing.to'ni.ae. M.L. fem.noun Wash- 
ingtonia a generic name; washingtoniae of 
Washingtonia. 

Rods, 0.69 l)y 1.61 microns, occurring 



singly or in short chains. Motile with 1 to 3 
polar flagella. Gram-negative. 

Green pigment in certain media. 

Gelatin: Liquefied. 

Potato dextrose agar colonies: Circular, 
smooth, convex, glistening, white to cream, 
butyrous, edges entire. 

Milk: No curd; peptonization with a green 
color in 7 days. 

Indole not produced. 

Nitrites not produced from nitrates. 

Hydrogen sulfide produced in minute 
amounts. 

Acid but no gas from glucose, fructose 
and L-arabinose in 24 hours; from galactose 
and xylose in 48 hours. No acid from sucrose, 
lactose, cellobiose, maltose, mannitol, 
D-sorbitol, glycerol, salicin or raffinose. 

Starch not hydrolyzed. 

Aerobic. 

Thermal death point between 47° and 
48° C. 

Source : Isolated from spots on the leaves 
of the palm, Washingtonia filifera. 

Habitat: Pathogenic on the Washington 
palm. 

102. Pseiidonioiias barker! (Berridge, 
1924) Clara, 1934. (Bacillus of pear blossom 
disease. Barker and Grove, Ann. Appl. 
Biol., 1, 1914, 94; Barker and Grove's or- 
ganism, Doidge, Ann. Appl. Biol., 4, 1917, 
50; B. barkeri Berridge, Ann. Appl. Biol., 11, 
1924, 73; Clara, Science, 75, 1934, 11.) 

bar'ker.i. M.L. gen. noun barkeri of 
Barker; named for B. T. P. Barker, one of 
the two men who first described this or- 
ganism. 

Description from Doidge (op. cit., 1917, 
50). 

Rods 0.5 to 0.8 by 2.0 to 4.0 microns. 
Motile with 1 to 4 polar flagella. Gram-nega- 
tive (Burkholder), not Gram-positive. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Agar: Growth is white, feeble, flat, glist- 
ening, smooth-edged. 

Broth: Slightly turbid in 24 hours. 

Milk: Slowly cleared. 

Nitrites not produced from nitrates. 

Indole not produced unless culture 
warmed. 



FAMILY IV. PSEUDOMONADACEAE 



137 



Starch slowly digested. 

Source: Barker made many cultures from 
blighted pear blossoms. Doidge received a 
culture from Barker. 

Habitat : Causes a blossom blight of pear. 

103. Pseudonionas betle (Ragunathan, 
1928) Burkholder, 1948. {Bacterium betle 
Ragunathan, Ann. Roy. Gard., Peradeniya, 
Ceylon, 11, 1928, 51; Burkholder, in Man- 
ual, 6th ed., 1948, 130.) 

bet'le. Malaj-an noun betle betel; M.L. 
indeclin.noun betle. 

Rods, 0.5 by 1.5 to 2.5 microns, occurring 
singly or in short chains. Non-motile. Gram- 
negative. 

Green pigment formed in nutrient gelatin 
and in broth. 

Gelatin: Liquefied. 

Bovril agar colonies: Honey-yellow, cir- 
cular at first, later echinulate. Raised, 
smooth and shiny. 

Bi-oth: Surface becomes cloud.y in 2 
days. Pellicle. 

No gas from lactose, maltose or sucro.se. 

Starch is reduced. 

Aerobic. 

Source: Five cultures isolated from leaf 
spots on the betel vine. 

Habitat: Pathogenic on the betel vine, 
Piper betle. 



104. Pseudomonas gladioli Severini, 
1913. (Annali d. Bot., Rome, 11, 1913, 420.) 

gla.di'o.li. L. gladiolus a small sword 
lily; M.L. mas.n. Gladiolus generic name of 
gladiolus; M.L. gen. noun gladioli of gladio- 
lus. 

Rods 0.6 by 2.3 to 2.8 microns. Motile 
with one or more polar flagella. Gram-nega- 
tive. 

A pale yellow, water-soluble pigment 
found, later orange. 

Gelatin colonies: Cream-colored, wart- 
like. Rapid liquefaction. 

Milk: Coagulated and slowly peptonized. 

Nitrites not produced from nitrates. 

Indole not produced. 

No gas. 

Aerobic. 

Optimum temperature between 28° and 
30° C. 



Habitat: Causes a corm rot of gladiolus 
and other tubers. 

105. Pseudomonas mellea Johnson, 
1923. (Jour. Agr. Res., 23, 1923, 489.) 

mel'le.a. L. adj. melleus pertaining to 
honey. 

Rods 0.6 by 1.8 microns. Encapsulated. 
Motile with 1 to 7 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Liquefied. 

Potato-glucose agar: Growth abundant, 
smooth, glistening, viscid, honey-colored. 

Broth: Turbid in 24 hours. Pellicle. 

Milk: Alkaline; clears. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Starch hydrolysis feeble. 

Growth inhibited by 4 per cent salt. 

Temperature relations: Optimum be- 
tween 26° and 28° C. Maximum, 36° C. 

Aerobic, facultative. 

Distinctive character: Differs from Pseu- 
domonas pseudozoogloeae in that it produces 
on tobacco a brown instead of a black spot 
with a halo, is orange-yellow in culture, and 
turns milk alkaline. 

Source: Isolated from brown rusty spots 
on tobacco in Wisconsin. 

Habitat: Pathogenic on leaves of tobacco, 
Nicotiana tobacum. 

106. Pseudomonas panacis (Nakata 
and Takimoto, 1922) Dowson, 1943. {Bac- 
terium panaxi Nakata and Takimoto, Bull. 
Agr. Sta. Chosen, 5, 1922, 1 ; Dowson, Trans. 
Brit. Mycol. Soc, S6, 1943, 10.) 

pa'na.cis. Gr. panax the plant heal-all; 
M.L. neut.noun Panax a generic name; 
M.L. gen. noun panacis of Panax. 

Description from Elliott (Bact. Plant 
Pathogens, 1930, 173). 

Rods 0.5 by 1.3 to 1.5 microns. Chains. 
Motile with 4 to 6 polar flagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Slight liquefaction. 

Agar colonies: White. 

Milk: Coagulated. 

No gas from sugars. 



138 



ORDER I. PSEUDOMONADALES 



Habitat: Causes a root rot of ginseng, 
Panax quinquefoliitm. 

107. Pseudomonas ribicola Bohn and 

Maloit, 1946. (Jour. Agr. Res., 73, 1946, 288.) 

ri.bi'co.la. M.L. noun Ribes generic name 
of currant; L. colo to dwell; M.L. fera.n. 
ribicola the currant dweller. 

Rods, 0.4 to 0.9 by 0.9 to 1.7 microns, 
occurring singly, in pairs and in hypha-like 
chains. Motile by 1 or more polar flagella. 
Gram-negative. 

Gelatin: Very slow liquefaction. 

Beef -extract agar colonies: Punctiform, 
smooth, translucent, white; edges entire. 

Beef -extract agar slant: Growth scant, 
filiform, glistening, translucent, white, 
slightly viscid. 

Broth: Slightly turbid; no ring or pellicle. 

Potato dextrose slants: Growth moder- 
ate, filiform, glistening, butyrous to viscid. 
Medium slightly yellow. Dirty pink pig- 
ment in old cultures. 

Milk: Slightly darkened, becoming alka- 
line. 

Nitrites produced from nitrates. 

Growth good in Uschinsky's and Fermi's 
solutions; yellow-green pigment produced. 
No growth in Cohn's and Ashby's mannitol 
solutions. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid from glucose, galactose, fructose, 
xylose and mannitol. 

Starch not hydrolyzed. 

Asparagine utilized as a carbon-nitrogen 
source. Tj^rosine oxidized. 

Not lipolytic. 

Temperature relations: Optimum, be- 
tween 20° and 25° C. Minimum, less than 
3.5° C. Maximum, between 30° and 32° C. 

Source: Six single-cell isolates from leaf 
spot of golden currant in Wyoming. 

Habitat: Pathogenic on Ribes aureum. 

108. Pseudomonas xanthochlora (Schuster, 
1912) Stapp, 1928. {Bacterium xanthochlorxim 
Schuster, Arbeit, a. d. Kaiserl. Biolog. 
Anstalt. f. Land. u. Forstw., 8, 1912, 452; 
Stapp, in Sorauer, Handbuch der Pflanzen- 
krankheiten, 2, 5 Aufl., 1928, 213.) 

xan.tho.chlo'ra. Gr. xanthus yellow; Gr. 



chlorus green; M.L. adj. xanthochlorvs yel- 
lowish green. 

Description from Erw. Smith (Bacteria 
in Rel. to Plant Dis., 3, 1914, 272). 

Rods 0.75 to 1.5 by 3.0 microns. Motile 
with 1 to 3 polar flagella. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Slow liquefaction. 

Agar colonies: Circular, slightly raised, 
yellow-white. 

Broth: Strong clouding in 24 hours. A 
white pellicle. 

Milk: Slow coagulation and clearing. 

Nitrites produced from nitrates. 

Indole produced after 10 days. 

Hydrogen sulfide produced slowly. 

Acid but no gas from glucose and galac- 
tose. 

Temperature relations: Optimum, 27° C. 
Minimum, 2° C. Maximum, 44° C. 

Source: Isolated from rotting potato 
tubers in Germany. 

Habitat : Pathogenic on potato tubers and 
a number of unrelated plants. 

109. Pseudomonas aleuritidis (McCul- 
loch and Demaree, 1932) Stapp, 1935. (Bac- 
terium aleuritidis McCulloch and Demaree, 
Jour. Agr. Res., 43, 1932, 339; Stapp, Bot. 
Rev., 1, 1935,408.) 

a.leu.ri'ti.dis. Gr. aleurites of wheaten 
flour; M.L. fem.noun Aleurites generic 
name; M.L. gen. noun aleuritidis of Aleu- 
rites. 

Rods 0.6 to 0.7 by 1.1 to 3.0 microns. 
Motile with 1 to 5 polar, rarely bipolar, 
flagella. Encapsulated. Gram-negative. 

Green fluorescent pigment produced in 
certain media. 

Gelatin: Not liquefied. 

Beef agar slants: Growth is thin, white 
and viscid. 

Broth: A heavy white surface growth in 
24 hours. Sediment. 

Milk: Becomes alkaline, but no separa- 
tion. 

Nitrites produced from nitrates. 

Indole test feebly positive. 

Hydrogen sulfide test feebly positive. 

Acid but no gas from glucose, galactose 
and glycerol. Slow acid production from 
sucrose, maltose and lactose. 



FAMILY IV. PSEUDOMONADACEAE 



139 



Starch hydrolysis feeble. 

Temperature relations : Optimum between 
27° and 28° C. Maximum, 37° C. 

Chemical tolerance: Optimum pH be- 
tween 6.2 and 6.8. pH range, 5.4 to 8.9. 

Source: Isolations from naturally infected 
timg oil trees in Georgia. 

Habitat: Pathogenic on the tung oil tree 
(Aleurites Jordi), on the bean {Phaseolus 
vulgaris) and the castor bean (Ricinus com- 
munis) . 

110. Pseudoinonas glycinea Coerper, 
1919. (Jour. Agr. Res., 18, 1919, 188.) 

gly.ci'ne.a. Gr. glycys sweet; M.L. 
f em. noun Glycine generic name of a legume ; 
M.L. adj. glycinea of the soybean. 

Rods 1.2 to 1.5 by 2.3 to 3.0 microns. 
Motile with polar flagella. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Not liquefied. 

Beef -peptone agar colonies: Appear in 
24 hours. Circular, creamy white, smooth, 
shining and convex. Margins entire. Buty- 
rous in consistency. 

Milk: Litmus turns blue and later a sepa- 
ration of the milk occurs. Casein not di- 
gested. 

Nitrites produced from nitrates (Burk- 
holder and Starr, Phytopath., 38, 1948, 498). 

Indole test feebly positive. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 32, 1942, 601). 

Acid from glucose and sucrose. 

Starch not hydrolyzed. 

Temperature relations: Optimum be- 
tween 24° and 26° C. Minimum, 2° C. Maxi- 
mum, 35° C. 

Aerobic, facultative. 

Comment: A variety of this species that 
differs slightly in morphology, action in 
milk and in chromogenesis has been de- 
scribed by Takimoto (Jour. Plant Prot., 
Tokyo, 14, 1927 556). It was isolated from 
leaf spots on soy bean in Formosa. 

Source: A number of cultures isolated 
from soybeans in Wisconsin. 

Habitat: Pathogenic on soybean. Glycine 
max {Soja niax) . 

111. Pseudonionas savastanoi (Erw. 
Smith, 1908) Stevens, 1913. (Bacterium 



savastanoi Erw. Smith, U. S. Dept. Agr. 
Plant Ind. Bull. 131, 1908, 31; Stevens, The 
Fungi which Cause Plant Diseases, 1913, 
33.) 

sa.vas.ta'no.i. Savastano patronymic; 
savastanoi of Savastano. 

Description from Brown (Jour. Agr. Res., 
U, 1932, 711). 

Rods 0.4 to 0.8 by 1.2 to 3.3 microns. 
Motile with 1 to 4 polar flagella. Gram- 
negative. 

Green fluorescent pigment found in cul- 
ture. 

Gelatin: No liquefaction. 

Beef agar colonies: White, smooth, flat, 
glistening, margins erose or entire. 

Broth: Turbid on the second day. No 
pellicle or ring. 

Milk: Becomes alkaline. 

Nitrites not produced from nitrates. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose, galactose 
and sucrose. 

Starch hydrolyzed. 

Temperature relations: Optimum be- 
tween 23° and 24° C. Minimum, 1° C. Max- 
imum, 32° C. 

Chemical tolerance: Optimum between 
6.8 and 7.0. Minimum, 5.6. Maximum, 8.5. 

Aerobic. 

Comment: A variety that differs but 
slightly from this species is described as 
pathogenic on ash, Fraxinus excelsior and F. 
americana, but not on olive. Produces a 
canker on ash. See Brown (Jour. Agr. Res., 
U, 1932, 721). 

Source: Smith isolated his cultures from 
olive galls collected in California. 

Habitat: Pathogenic on olive. 

112. Pseudoinonas tonelliana (Ferra- 
ris, 1926) Burkholder, 1948. {Bacterixim to- 
nellianum Ferraris, Trattato di Patologia e 
TerapiaVegetale,3rded.,/, 1926, 104; Burk- 
holder, in Manual, 6th ed., 1948, 132.) 

to.nel.li.a'na. M.L. adj. tonellianus per- 
taining to Tonelli; named for A. Tonelli. 

Description from C. O. Smith (Phyto- 
path., 18, 1928, 503) unless otherwise noted. 

Rods 0.5 to 0.6 by 1.5 to 2.5 microns. 
Motile with 1 to 3 polar flagella. Gram- 
negative (Adam and Pugsley, Jour. Dept. 
Agr. Victoria, 32, 1934, 304). 



140 



ORDER I. PSEUDOMONADALES 



Gelatin: No liquefaction. 

Potato glucose agar colonies: Flat, circu- 
lar, shining; margins somewhat undulated. 

Broth: Dense clouding with partial pel- 
licle. 

Milk: Alkaline. No separation. 

Nitrites not produced from nitrates 
(Adam and Pugsley). 

Indole produced. Not produced (Adam 
and Pugsley). 

Acid but no gas from glucose and sucrose. 
No acid from lactose (Adam and Pugsley). 

Starch not hydrolyzed (Adam and Pugs- 
ley). 

Comment: Pseudomonas savastanoi is 
similar in culture but is not pathogenic on 
oleanders. 

Source: Both Ferraris and C. O. Smith 
isolated the pathogen from galls on olean- 
der. 

Habitat: Pathogenic on oleander, Nerium 
oleander. 

113. Pseudomonas cissicola (Takimoto, 
1939) Burkholder, 1948. (Aplanobacter cissi- 
cola Takimoto, Ann. Phytopath. Soc. Japan, 
9, 1939, 43; Burkholder, in Manual, 6th ed., 
1948, 134.) 

cis.si'co.la. Gr. cissus ivy; M.L. fem.noun 
Cissiis generic name of flowering plant; 
L. -cola dweller; M.L. fem.noun cissicola 
Cissus dweller. 

Rods 0.5 to 0.9 by 1.0 to 2.0 microns. 
Non-motile. Encapsulated. Gram-negative. 

Green fluorescent pigment formed in 
Uschinsky's solution. 

Gelatin: No liquefaction. 

Potato-extract agar colonies: Circular, 
conve.x, smooth, dirty white. 

Broth: Feeble clouding followed by pre- 
cipitation of pellicle and rim. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

No acid nor gas from sucrose, glucose, lac- 
tose or glycerol. 

Starch not hydrolyzed. 

Salt toleration, 3 per cent. 

Temperature relations: Optimum, 30° C. 
Minimum, 10° C. Maximum, 35° C. Ther- 
mal death point between 49° and 50° C. 

Source: Isolated from black spots on 



leaves of Japanese ivy, Cissus japonica, in 
Japan. 

Habitat: Pathogenic only on Cissus ja- 
ponica. 

114. Pseudomonas ealendulae (Taki- 
moto, 1936) Dowson, 1943. (Bacterium 
ealendulae Takimoto, Ann. Phytopath. Soc. 
Japan, 5, 1936, 341; Dowson, Trans. Brit. 
Mycol. Soc, 26, 1943, 9.) 

ca.len'du.lae. L. fem.pl. noun calendae 
(Kalendae) The Calends, first day of month; 
M.L. fem. dim. noun Calendula generic name 
of a flowering plant; M.L. gen. noun ealen- 
dulae of Calendula. 

Rods 0.5 by 1.0 to 2.0 microns. Motile 
with 1 to 3 polar flagella. Gram-negative. 

Green fluorescent pigment produced in 
Uschinsky's and in Cohn's solutions. 

Gelatin: Not liquefied. 

Agar colonies: Circular, smooth, flat, 
dirty white. 

Broth: Turbid. 

Milk: No coagulation. 

Nitrites not produced from nitrates. 

Indole produced in small amount. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose and glycerol. 
No acid from lactose or sucrose. 

Starch not hydrolyzed. 

Temperature relations: Optimum be- 
tween 27° and 30° C. Minimum between 0° 
and 7° C. Maximum, 37° C. 

Habitat: Pathogenic on marigolds, Calen- 
dula officinalis. 

115. Pseudomonas cichorii (Swingle, 
1925) Stapp, 1928. {Phjtomonas cichorii 
Swingle, Phytopath., 15, 1925, 730; Stapp, in 
Sorauer, Handbuch der Pfianzenkrank- 
heiten, 2, 5 Aufll., 1928, 291; Pseudomonas 
endiviae Kotte, Phyt. Ztschr., 1, 1930, 609; 
Bacterium formosanum Okabe, Jour. Soc. 
Trop. Agr., Formosa, 7, 1935, 65.) 

ci.cho'ri.i. Gr. cichora (pi.) succory, chi- 
cory; L. cichoriutn chicory; M.L. neut.noun 
Cichoriutn generic name of flowering plant; 
M.L. gen. noun cichorii of chicory. 

Description from Clara (Cornell Agr. 
Exp. Sta. Mem. 159, 1934, 26) which is a de- 
scription of a culture of Pseudomonas endi- 
viae from Kotte. Swingle's description is 
very meager. 



FAMILY IV. PSEUDOMONADACEAE 



141 



Rods 0.75 to 1.5 by 1.5 to 3.75 microns. 
Motile with 1 or 2 polar fiagella. Gram- 
negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: No liquefaction. 

Beef -extract agar colonies: Circular, 
grayish white with bluish tinge, raised with 
slightly irregular edges. 

Broth: Turbid in 36 hours with a smooth, 
viscous pellicle. 

Milk: Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

H3'drogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, Phj^- 
topath., 32, 1942, 601). 

Acid but no gas from glucose, galactose 
fructose, mannose, arabinose, xylose, man- 
nitol and glycerol. Alkaline production from 
salts of acetic, citric, lactic, malic, succinic 
and tartaric acids. Rhamnose, maltose, 
sucrose, lactose, raffinose and salicin not 
utilized. 

Starch not hydrolyzed. 

Slight growth in broth plus 6 per cent 
NaCl. 

Chemical tolerance: Optimum pH, be- 
tween 6.8 and 7.1. Minimum, between 5.0 
and 5.3. Maximum, between 9.2 and 9.4. 
(Kotte, op. cit., 2, 1930, 453). 

Aerobic, facultative. 

Source: Isolated from rot of French en- 
dive, Cichorium intybus, by Swingle and by 
Okabe, and from C. endivia by Kotte. 

Habitat: Pathogenic on endive, lettuce 
and larkspur. 

116. Pseiidomonas nectarophila 

(Doidge, 1917) Rosen and Bleeker, 1933. 
{Bacterium nectar ophilum Doidge, Ann. 
Appl. Biol., J^, 1917, 73; Rosen and Bleeker, 
Jour. Agr. Res., ^6, 1933, 98.) 

nee. ta.ro 'phi. la. Gr. nectar nectar; Gr. 
adj. philus loving; M.L. adj. nectarophilns 
nectar-loving. 

Rods 0.5 to 0.7 by 0.6 to 1.5 microns. 
Motile with 1 to 5 polar flagella. Encapsu- 
lated. Gram-negative. 

Green fluorescent pigment produced in 
culture. 

Gelatin: No liquefaction. 



Nutrient agar colonies: Yellowish white, 
wet-shining, smooth; margins irregular. 

Broth: Heavy turbidity in 24 hours. 
Sediment. 

Milk: Cleared. 

Nitrites not produced from nitrates. 

Indole not produced. 

Acid from glucose and galactose. No acid 
from sucrose. 

Starch hydrolysis feeble. 

Optimum temperature between 25° and 
30° C. 

Aerobic, facultative. 

Distinctive character : Differs from Pseu- 
domonas barkeri in that it does not liquefy 
gelatin nor produce indole. Produces cap- 
sules. 

Source : Isolated from blighted pear blos- 
soms in South Africa. 

Habitat: Pathogenic on pear blossoms. 

117. Pseudomonas viburni (Thornberry 
and Anderson, 1931) Stapp, 1935. (Phyto- 
monas viburni Thornberry and Anderson, 
Phytopath., 21, 1931, 912; Stapp, Bot. Rev. 
1, 1935,407.) 

vi.bur'ni. L. viburnum waj' -faring tree; 
M.L. neut.noun Viburnum name of a genus 
of flowering plants; M.L. gen. noun viburni 
of Viburnum. 

Rods 0.5 to 1.0 by 1.0 to 2.0 microns. 
Encapsulated. Motile with 2 to 4 polar 
flagella. Gram-negative (Burkholder); not 
Gram-positive as stated in original. 

Green fluorescent pigment produced in 
culture (Burkholder). 

Gelatin: No liquefaction. 

Glucose beef-extract colonies: Dull gray, 
circular, edges entire. 

Broth: Turbid with pellicle. 

Milk: Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 32, 1942, 601). 

Acid from glucose and galactose but not 
sucrose (Burkholder). 

Starch: No hydrolysis. 

Slight growth in 3.5 per cent salt (Burk- 
holder). 

Temperature relations: Optimum, 25° C. 
Minimum, 12° C. Maximum, 35° C. 



142 



ORDER I. PSEUDOMONADALES 



Aerobic. 

Source: Isolated from angular leaf spots 
and stem lesions on arrow-wood, Viburnum 
opulus, etc. 

Habitat: Pathogenic on Viburnum spp. 

118. Pseudomonas mori (Boyer and 
Lambert, 1893) Stevens, 1913. {Bacterium 
mori Boyer and Lambert, Compt. rend. 
Acad. Sci., Paris, 117, 1893, 342; Bacterium 
mori Boyer and Lambert emend. Erw. Smith, 
Science, 31, 1910, 792; Stevens, The Fungi 
which Cause Plant Diseases, 1913, 30.) 

mo'ri. Gr. morum the black mulberry; 
M.L. fem.noun Morus the generic name of 
mulberry; M.L. gen. noun mori of the mul- 
berry. 

Description from Smith (op. cit., 1910, 
792). 

Rods 0.9 to 1.3 by 1.8 to 4.5 microns. 
Motile with a polar flagellum. Gram-nega- 
tive. 

Green fluorescent pigment produced in 
culture. 

Gelatin: Not liquefied. 

Agar colonies: White, slow-growing, 
smooth, flat; edges entire, becoming undu- 
late. 

Milk: Becomes alkaline and clears. 

Nitrites not produced from nitrates. 

Indole test negative or feebly positive. 

Hydrogen sulfide not produced (Okabe, 
Jour. Soc. Trop. Agr., 5, 1933, 166). 

No growth in broth plus 4 per cent salt 
(Okabe, loc. cit.). 

No gas from carbohydrates. 

Temperature range, 1° C. to 35° C. 

Source: Smith isolated the pathogen from 
blighted shoots of mulberry from Georgia. 
Also received cultures from Arkansas and 
the Pacific Coast. 

Habitat: Pathogenic on mulberry, Morus. 

119. Pseudomonas stizolobii (Wolf, 1920) 
Stapp, 1935. (Aplanobactcr stizolobii Wolf, 
Phytopath., 10, 1920, 79; Stapp, Bot. Rev., 
1, 1935, 405.) 

sti.zo.lo'bi.i. Gr. stizo to prick, tat- 
too; Gr. dim. labium a small lobe; M.L. 
neut.noun Stizolobium plant generic name; 
M.L. gen. noun stizolobii of Stizolobium. 

Rods 0.6 to 0.7 by 1.0 to 1.6 microns. 
Non-motile (Wolf, op. cit., 1920, 79). Motile 



with a short polar flagellum (McCulloch, 
Phytopath., 18, 1928, 460). Encapsulated. 
Gram-negative. 

Gelatin: No liquefaction. 

Agar colonies: Circular, smooth, white, 
raised and opaque. Margins entire to 
slightly undulate. 

Broth: Slightly turbid throughout. No 
pellicle or ring. 

Milk: Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

No acid or gas in peptone broth plus 
sugars. 

Starch not hydrolyzed. 

Optimum temperature between 25° and 
28° C. 

Distinctive characters: Differs from 
Pseudomonas sojae (Pseudomonas glycinea) 
in the smaller size of cell, the absence of a 
pellicle and dense clouding of broth. The 
pathogen does not infect soybean. 

Source: Isolated from the leaf spot of 
velvet bean. 

Habitat: Pathogenic on velvet bean, 
Stizolobium deeringianium. 

120. Pseudomonas viciae Uyeda, 1915. 
(Uyeda, in Takimoto, Jour. Plant Protect., 
Japan, 2, 1915, 845.) 

vi'ci.ae. L. vicia vetch; M.L. fem.noun 
Vicia generic name of vetch; M.L. gen.noim 
viciae of vetch. 

Rods 0.5 to 0.8 by 1.2 to 2.0 microns. 
Motile with 2 to 4 polar flagella. Reported 
as Gram-positive; however, probably in 
error. No cultures are available for a retest 
of this character. 

Green fluorescent pigment produced in 
culture. 

Gelatin colonies: Pale white, glistening, 
finally turning brown. No liquefaction. 

Milk: Coagulates and clears. 

Nitrites not produced from nitrates. 

Hj'drogen sulfide not produced. 

Aerobic, facultative. 

Habitat: Pathogenic on the broad bean 
(Vicia f aba), the turnip (Brassica rapa), the 
carrot (Da^lcus carota) and the sweet potato 
(Ipomoea batatas) . 

121. Pseudomonas alliieola (Burk 
holder, 1942) Starr and Burkholder, 1942. 



FAMILY IV. PSEUDOMONADACEAE 



143 



(Phytomonas alliicola Burkholder, Phyto- 
path., 32, 1942, 146; Starr and Burkholder, 
Phytopath., ibid., 601.) 

al.li.i'co.la. L. allium onion; L. -cola 
dweller; M.L. fern. noun alliicola onion 
dweller. 

Rods 0.7 to 1.4 by 1.05 to 2.8 microns. 
Motile with 1 to several polar flagella, at 
times bipolar. Gram-negative. 

Gelatin: Liquefied. 

Beef -extract peptone agar streaks : Mod- 
erate in growth, white at first, later dirty 
in appearance, edges wavy, consistency vis- 
cid. Medium deep brown. 

Potato-glucose agar frequently becomes 
greenish. 

Broth: Turbid with light pellicle. Brown. 

Milk: Cleared and litmus reduced. Neu- 
tral. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Lipolytic action very strong. 

Acid but no gas from 1-arabinose, d-xy- 
lose, rhamnose, glucose, d-galactose, fruc- 
tose, d-lactose, maltose, sucrose, glycerol, 
mannitol and salicin. Alkali from salts of 
acetic, citric, formic, hippuric, lactic, malic, 
succinic and tartaric acids. 

Starch not hydrolyzed. 

Slight growth in broth plus 4 per cent 
salt. 

Aerobic. 

Temperature relations: Optimimi, 30° C. 
Minimum, 5° C. Maximum, 41° C. 

Source: Seven isolates from storage rot 
of onion bulbs. 

Habitat: Pathogenic on onion bulbs, Al- 
lixun cepa. 

122. Pseiidonionas gardeniae Burk- 
holder and Pirone, 1941. (Phytopath., 31, 
1941, 194.) 

gar.de'ni.ae. L. Garden patronymic; 
M.L. fem.noun Gardenia plant generic 
name; M.L. gen. noun gardeniae of Gardenia. 

Rods 0.75 by 2.4 microns. Motile with 
1 to 2 polar flagella. Gram-negative. 

Gelatin: Liquefied. 

Beef -extract peptone agar colonies: 
Growth fair, white to dirty gray and viscid. 
Medium becoming dark brown. 

Potato-glucose agar: No brown color. 



Broth: Turbid with pellicle. Dark brown. 

Milk: Soft curd with pellicle. Clears in 
zones. Litmus reduced. 

Nitrites produced from nitrates. 

Hydrogen sulfide not produced. 

Indole not produced. 

Acid from glucose, galactose, xylose, 
rhamnose, sucrose, maltose, mannitol, 
glycerol and salicin. Alkali produced from 
the salts of citric, malic, malonic, succinic, 
tartaric and hippuric acids. Good growth 
in tyrosine and in asparagine broth. 

Starch not hydrolyzed. 

Aerobic. 

Source: Eight isolates from leaf spots of 
gardenias in New Jersey. 

Habitat : Pathogenic on leaves of Gardenia 
jasminoides. 

123. Pseudonionas caryophylli (Burk- 
holder, 1942) Starr and Burkholder, 1942. 
{Phytomonas caryophylli Burkholder, Phy- 
topath., 32, 1942, 143; Starr and Burk- 
holder, ibid., 601.) 

ca.ry.o'phyl.li. Gr. caryophyllum nut 
leaf, the clover tree; M.L. mas. noun 
caryophyllus specific epithet in Dianthus 
caryophyllus , the clove-pink or carnation; 
M.L. gen. noun caryophylli of the carnation. 

Rods 0.35 to 0.95 by 1.05 to 3.18 microns. 
At times slightly curved. Motile with 1 to 
several polar flagella. Frequently bipolar. 
Gram-negative. 

Gelatin: Liquefaction after 3 to 4 weeks. 

Potato glucose agar colonies: 3 to 4 mm in 
diameter, circular, smooth, glistening, 
edges entire. Color is tan to gray-mauve. 
Old culture dark brown. Consistency buty- 
rous. 

Broth: Turbid with a white sediment. 

Milk: Litmus slowly becomes blue. Slight 
reduction at bottom of tube. No clearing. 

Nitrites produced from nitrates. Also 
ammonia and gas are produced in a syn- 
thetic nitrate medium. Asparagine, KNO3 
and NH4H2PO4 can be utilized. 

Indole not produced. 

Hydrogen sulfide not produced. 

Lipolytic action slight to moderate. 

Acid from 1-arabinose, d-xylose, rham- 
nose, glucose, d-galactose, fructose, d-lac- 
tose, maltose, sucrose, glj^cerol, mannitol 
and salicin. Alkali with sodium salts of 



144 



ORDER I. PSEUDOMONADALES 



acetic, citric, formic, hippuric, lactic, malic, 
maleic, succinic and tartaric acids. 

Starch not hydrolyzed. 

Aerobic. 

Temperature relations: Optimum be- 
tween 30° and 33° C. Minimum, 5° C. or 
less. Maximum, 46° C. 

Slight growth in broth plus 3.5 per cent 
salt. 

Source: Isolated first by L. K. Jones and 
later by W. H. Burkholder from dying car- 
nation plants from Spokane, Washington. 
Twelve isolates used in description. 

Habitat: Pathogenic on roots and stalks 
of the carnation, Dianthus caryophyllus . 



35° and 37° C. Minimum, 10° C. Maximum, 
41° C. 

Pathogenicity readily lost in culture. 

Comment: A variety that turns litmus 
milk and cream red has been described by 
Erw. Smith (Bact. in Relation to Plant 
Diseases, S, 1914, 282). It was isolated by 
J. A. Honing from diseased tobacco plants 
in Medan, Sumatra. 

Source: Isolated from brown-rot of 
solanaceous plants. 

Habitat: Soil pathogen in warm, moist 
climates attacking numerous species of 
plants, especially potato, tobacco and 
tomato. 



124. Pseudonionas solanacearuni (Erw. 
Smith, 1896) Erw. Smith, 1914. {Bacillus 
solanacearuni Erw. Smith, U. S. Dept. Agr., 
Div. Veg. Phys. and Path., Bull. 12, 1896, 
10; Erw. Smith, Bacteria in Relation to 
Plant Diseases, 3, 1914, 178.) 

so.la.na.ce.a'rum. L. solarium the night- 
shade; -aceae familial ending; M.L. fem.pl. 
noun Solanaceae the nightshade family; 
M.L. fem.pl. gen. n. solanacearuni of the 
Solanaceae. 

Rods 0.5 to 1.5 microns. Motile with a 
polar flagellum. Gram-negative. 

Gelatin: Nakata (Jour. Sci. Agr. Soc. 
Tokyo, 29^, 1927, 216) states there are two 
forms, one of which shows slight liquefac- 
tion. The other shows no liquefaction. 

Agar colonies: Small, irregular, roundish, 
smooth, wet-shining, opalescent, becoming 
brown. 

Broth: Slight pellicle. Broth turns brown. 

Milk: Cleared without precipitation of 
casein. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced (Burk- 
holder). 

Glucose, sucrose, glycerol, sodium citrate, 
peptone, tyrosine, asparagine and glutamic 
acid are utilized (Mushin, Austral. Jour. 
Expt. Biol, and Med., 16, 1938, 325). 

Nitrogen sources utilized are ammonia, 
nitrates (KNO3), asparagine, tyrosine, pep- 
tone and glutamic acid, but not potassium 
nitrite (Mushin, loc. cit.). 

Starch not hydrolyzed. 

Temperature relations: Optimum between 



125. Pseudonionas castaneae (Kawa- 
mura, 1934) SSvulescu, 1947. {Bacterium 
castaneae Kawamura, Ann. Phytopath. Soc. 
Japan, 3, 1934, 15; SSvulescu, Anal. Acad. 
Romane, III, 22, 1947, 11.) 

cas.ta'ne.ae. Gr. castanum the chest- 
nut tree; L. castanea the chestnut; M.L. 
fem.noun Castanea generic name of chest- 
nut; M.L. gen. noun castaneae of the chest- 
nut. 

Rods 0.8 to 1.2 by 1.0 to 1.8 microns. 
Motile with 1 to 5 polar flagella. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Beef agar colonies: White, circular, edges 
slightly undulate, viscid. 

Milk: No coagulation. Peptonized. 

Acid but no gas from glucose, sucrose and 
glycerol. No acid from lactose. 

Temperature relations : Optimum between 
25° and 27° C. Minimum, 3° C. Maximum, 
35° C. 

Aerobic, facultative. 

Habitat: Causes water-soaked spotting 
on leaves and shoots of chestnut, Castanea. 

126. Pseudonionas passiflorae (Reid, 
1939) Burkholder, 1948. {Phytomonas passi- 
florae Reid, New Zealand Jour. Sci. and 
Tech., 22, 1939, 264a; Burkholder, in Man- 
ual, 6th ed., 1948, 138.) 

pas.si.flo'rae. L. passio passion; L. flos, 
floris a flower; M.L. fem.noun Passiflora 
generic name of passion flower; M.L. 
gen. noun passiflorae of the passion flower. 

Rods 0.2 to 0.5 by 1.2 to 3.2 microns- 



FAMILY IV. PSEUDOMO^^ADACEAE 



145 



Motile with 1 to 5 polar flagella. Encapsu- 
lated. Gram-negative. 

Gelatin: Liquefied. 

Beef -peptone agar colonies: Small, flat, 
.smooth, dry, shining, translucent, graj^ish 
and butyrous. 

Broth: Turbid in 4 days. Transient pel- 
licle. 

Milk: Slightly alkaline. No coagulation 
nor clearing. 

Nitrites not produced from nitrates. No 
growth on synthetic nitrate agar. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid reaction occurs in galactose, starch 
and sucrose. No gas. 

Starch not hj-drolyzed. 

Source : From diseased leaves and fruit of 
the passion fruit in New Zealand. 

Habitat: Pathogenic on Passiflora edulis. 

127. Pseudomonas seininuni Caylej', 
1917. (Jour. Agr. Sci., 8, 1917, 461.) 

se'mi.num. L. semen, sennnis seed; L. 
gen.pl. semimim of seeds. 

Rods 1.0 by 4.0 to 5.0 microns. Spore- 
like bodies present. Encapsulated. Motile 
with a single flagellum. Reported as Gram- 
po.sitive; however, probablj^ in error. No 
cultures are available for a retest of this 
character. 

Gelatin: Rapid liquefaction. 

Agar colonies: White, more or less circu- 
lar, transparent, spreading. 

Broth: Turbid. Pellicle. 

Litmus milk: Milk becomes clear and 
apricot color. 

Nitrites produced from nitrates. 

Acid but no gas from glucose and sucrose. 
No acid from lactose. 

Starch: No hydrolysis. 

Optimum temperature, 25° C. 

Aerobic, facultative. 

Source: Isolated from seeds, stems and 
pods of diseased peas in England. 

128. P.seiidonionas vitiswoodrowii Pa- 
id and Kulkarni, 1951. (Pseudomonas ritis- 
woodrowii (sic) Patel and Kulkai'ui, Curr. 
Sci.,^0, 1951, 132.) 

vi.tis.wood.ro'wi.i. L. fem.noun vitis 
a vine; M.L. fem.noun Vitis a generic name; 



Woodrow patronymic; M.L. gen. noun woo(/- 
rowii of Woodrow. 

Rods 0.8 by 1.5 microns. Motile with 
a single polar flagellum. Gram-negative. 

Gelatin: Liquefied. 

Potato dextrose agar colonies: Circular, 
capitate with margins entire. Pale, dull 
gray. 1.2 cm in diameter in 7 daj's. 

Broth: Turbid. 

Potato cylinders: Scant growth. Medium 
dark gray. 

Milk : Litmus reduced and casein digested. 

Hydrogen sulfide produced. 

Loefiler's blood serum: Liquefied. 

Indole not produced. 

Synthetic asparagine medium. No growth. 

Methyl red test negative; acetylmethyl- 
carbinol not produced. 

Nitrites not produced from nitrates. 

Acid but no gas from glucose, lactose and 
sucrose, but no growth in salicin. 

Salt tolerance: Up to 1 per cent. 

Optimum temperature between 25° and 
28° C. 

Aerobic. 

Source: Isolated from leaves of Vitis 
woodrowii in India. 

Habitat : Pathogenic on V. woodrowii but 
not on V. vinifera. 

129. Pseudomonas fabae (Yu, 1936) 
Burkholder, 1948. (Phytomonas fabae Yu, 
Bull, of the Chinese Bot. Soc, 2, 1936, 34; 
Burkholder, in Manual, 6th ed., 1948, 139.) 

fa'bae. L. faba the horse bean; M.L. 
gen. noun /aftoe of the hor.se bean. 

Rods 0.8 to 1.1 by 1.1 to 2.8 microns. Mo- 
tile with 1 to 4 polar flagella. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Nutrient agar colonies: Circular, entire, 
viscid, glistening, raised, smooth to 
wrinkled, white to salmon. Medium amber. 

Broth: Turbid after 12 hours. Pellicle. 

Milk: Growth slow. Clears. 

Nitrites produced from nitrates. 

Indole production slight. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose. No acid 
nor gas developed from arabinose, xylose, 
fructose, galactose, sucrose, lactose, mal- 
tose, raffinose, dextrin, inulin, mannitol or 



146 



ORDER I. PSEUDOMONADALES 



adonitol in a 1 per cent Bacto-peptone 
broth. 

Starch: Very weak diastatic action. 

Temperature relations: Optimum, 35° C. 
Minimum, 4° C. Maximum between 37° and 
38° C. Thermal death point between 52° and 
53° C. 

Aerobic. 

Growth retarded in 2 per cent salt. Very 
slight growth in 3 per cent salt. 

Source: From diseased broad beans at 
Nanking, China. 

Habitat : Pathogenic on broad or Windsor 
bean, Vicia faba. 

130. Pseudomonas astragali (Taki- 
moto, 1930) Savulescu, 1947. {Bacterium 
astragali Takimoto, Jour. Plant Protect., 
17, 1930, 732; SSvulescu, Anal. Acad. Ro- 
mane. III, ££, 1947, 11.) 

as.tra'ga.li. Gr. astragalus a vertebra, 
also a leguminous plant; M.L. mas. noun 
Astragalus a generic name; M.L. gen. noun 
astragali of Astragalus. 

Description translated by Dr. K. To- 
gashi. 

Rods 0.7 to 0.8 by 1.2 to 2.2 microns. 
Motile, with 1 or 2 flagella. Gram-negative. 

Gelatin: Liquefied. 

Agar plates: Growth somewhat slow, 
colorless or grayish white, entire margins, 
more or less aqueous, butyrous. 

Uschinsky's medium: Growth vigorous, 
turbid, not viscid; ring and sediment. 

Milk: No coagulation of casein, slow di- 
gestion. Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced in small 
amount. 

No acid or gas from glucose, sucrose, 
lactose or glycerol in broth. 

Starch not hydrolyzed. 

Temperature relations: Minimum, below 
5° C. Maximum, 33° C. Thermal death 
point between 50° and 51° C. 

Aerobic. 

Source: Species isolated from Astragalus 
sp. 

Habitat: Causes a black leaf -spot of 
Astragalus sp. 

131. Psevidomonas colurnae (Thorn- 



berry and Anderson, 1937) Burkholder, 
1948. {Phytomonas colurnae Thornberry and 
Anderson, Phytopath., 37, 1937, 948; Burk- 
holder, in Manual, 6th ed., 1948, 139.) 

co.lur'nae. L. fem.noun corylus the hazel 
or filbert; L. adj. colurnus (transposition of 
corulnus) pertaining to hazel. 

Rods 0.8 to 1.0 by 1.0 to 1.8 microns. 
Single, in pairs or chains. Encapsulated. 
Motile with 1 to 2 polar flagella. Gram- 
negative. 

Gelatin: Liquefied. 

Glucose agar slants: Growth filiform, 
raised, dull, smooth, opaque and viscid. 

Broth: Moderate turbidity. Ring. 

Milk: Peptonization complete with acid 
production. No reduction of litmus nor 
coagulation. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

No appreciable amount of gas from 
xylose, glucose, sucrose or glycerol. 

Starch hydrolyzed. 

Temperature relations: Optimum, 21° C. 
Minimum, 5° C. Maximum, 35° C. Thermal 
death point, 50° C. 

Aerobic. 

Source: From leaves and young stems of 
the Turkish hazelnut in Illinois. 

Habitat: Pathogenic on the Turkish 
hazelnut, Corylus colurna. 

132. Pseudomonas iridicola (Taki- 
moto, 1931) Stapp, 1935. {Bacterium iridicola 
Takimoto, Fungi, Nippon Fungological 
Soc, 1, 1931, 24; Stapp, Bot. Rev., 1, 1935, 
408.) 

i.ri.di'co.la. Gr. iris, iridis the rainbow, 
the plant iris; M.L. fem.noun 7ns generic 
name; L. -cola dweller; M.L. fem.noun 
iridicola iris dweller. 

Rods 0.7 to 0.8 by 1.2 to 2 microns. 
Motile with 1 to 3 polar flagella. Gram- 
negative. 

Gelatin: Liquefied. 

Beef agar colonies: White, circular, 
raised or convex. 

Milk: Clears without coagulation. 

No acid or gas from carbohydrates. 

Starch digested. 

Temperature relations: Optimum, 38° C. 
Minimum, 4° C. 



FAMILY IV. PSEUDOMONADACEAE 



147 



Source : Isolated from a brown leaf spot of 
iris. 

Habitat : Pathogenic on Iris tectorum and 
Iris japo7iica. 

133. Pseudomonas levistici Oster- 
walder, 1909. (Cent. f. Bakt., II Abt., 25, 
1909, 260.) 

le.vis'ti.ci. L. neut.noun ligusticum a 
Ligurian plant, lovage; L. neut.noun le- 
visticum a corruption of ligusticum; M.L. 
neut.noun Levisticum generic name of 
lovage; M.L. gen. noun levistici of Levisti- 
cum. 

Rods 0.5 to 0.7 by 1.1 to 1.5 microns. 
Motile with a polar flagellum. Gram-nega- 
tive. 

Gelatin: Colonies greenish white. Li- 
quefied. 

Nutrient agar: Good growth at room 
temperature. Yellowish white. 

Broth: Pellicle. 

Indole produced. 

Hydrogen sulfide not produced. 

Source : Isolated from spots on the leaves 
of lovage. 

Habitat: Pathogenic on lovage, Levisti- 
cum officinale. 

134. Pseudomonas niaublaucii (Foex 
and Lansade, 1936) SHvulescu, 1947. {Bac- 
terium maublancii Foex and Lansade, 
Compt. rend. Acad. Sci., Paris, 202, 
1936,2174; Savulescu, Anal. Acad. Romane, 
III, 22, 1947, 11.) 

mau.blan'ci.i. Maublanc, patronymic; 
M.L. gen. noun maublancii of Maublanc. 

Rods 0.4 by 1.3 microns. Motile with 1 
to 3 polar flagella. Gram-negative. 

Gelatin: Liquefied. 

Gelatin colonies: Round, translucent, 
margins entire. 

Broth: Thin pellicle. 

Milk: Not coagulated; clears. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Carbohydrates not fermented. 

Ammonia produced. 

Growth in Fermi's solution, not in Us- 
chinsky's solution. 

Source: Isolated from rotting vascular 
and parenchymatic tissue of banana stalks. 



Habitat: Causes a disease of the banana 
plant. 

135. Pseudomonas polygoni (Thorn- 
berry and Anderson, 1937) Burkholder, 
1948. (Phytomonas polygoni Thornberry 
and Anderson, Phytopath., 27, 1937, 947; 
Burkholder, in Manual, 6th ed., 1948, 140.) 

po.ly'go.ni. Gr. polygonum knot weed; 
M.L. neut.noun Polygonum generic name; 
M.L. gen. noun polygoni of Polygonum. 

Rods 0.5 to 1.5 by 1.5 to 2.5 microns. 
Motile with 2 to 8 bipolar flagella. Encap- 
sulated. Gram-positive (?). Other species 
reported by these investigators as Gram- 
positive have proved to be Gram-negative 
on a retest (Burkholder). 

Gelatin: Liquefied. Brown. 

Glucose agar slant: Abundant, filiform, 
flat, dull, smooth, pale olive-gray, bvity- 
rous. Medium turns brown. 

Broth: Turbid. Pellicle. 

Milk: Alkaline and clears. Litmus not re- 
duced. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

No appreciable amount of gas from car- 
bohydrates. 

Starch: No hydrolysis. 

Temperature relations: Optimum, 18° C. 
Minimum, 7° C. Maximum, 35° C. 

Aerobic. 

Source: From diseased leaves of Poly- 
gomim convolvulus in Illinois. 

Habitat: Pathogenic on black bindweed, 
Polygonum convolvulus. 

136. Pseudomonas radiciperda (Javo- 
ronkova, 1932) Savulescu, 1947. (Bacterium 
radiciperda Javoronkova, Bull. Plant Pro- 
tect., Leningrad, Ser. II, 5, no. 1, 1932, 161; 
savulescu. Anal. Acad. Romane, III, 22, 
1947, 11.) 

ra.di.ci.per'da. L. radix, radicis root; L. 
perdo to destroy; M.L. fem.noun radiciperda 
the root destroyer. 

Description from Javoronkova (Rev. App. 
Myc, 11, 1932, 652). 

Rods 0.8 by 1.0 to 2.0 microns. Encapsu- 
lated. Motile by means of 1 or 2 polar fla- 
gella. Gram-negative. 

Gelatin: Liquefied. 



148 



ORDER I. PSEUDOMONADALES 



Beef-peptone agar colonies: Round, 
smooth, shining, white to pale yellow. 

Milk: Peptonized. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid but no gas from carbohydrates. 

Optimum temperature between 23° and 
25° C. 

Aerobic. 

Habitat: Causes a root rot of red clover 
{Trifolium praiense) , lentils (Lens escu- 
lenta) and lucerne. 

137. Pseudomonas cattleyae (Pava- 
rino, 1911) SS,vulescu, 1947. {Bacterium 
cattleyae Pavarino, Atti R. Acad. Naz. 
Lincei Rend. CI. Sci. Fis., Mat. e Nat., 20, 
1911, 233; Savulescu, Anal. Acad. Romane, 
III, 22, 1947, 11.) 

catt'ley.ae. M.L.fem.noun Cattleya a 
generic name; M.L. gen. noun cattleyae of 
Cattleya. 

Description from Ark and Thomas (Phy- 
topath., 36, 1946, 697). 

Rods, 0.4 to 0.6 by 2.4 microns, occurring 
singly or in pairs. Motile by means of 1 or 
2 bipolar flagella. Gram-negative. 

Gelatin: No liquefaction. 

Beef -extract peptone agar colonies: 
Large, entire, smooth, with criss-cross 
markings. Grayish white and butyrous. 

Broth: Turbid in 24 hours with very deli- 
cate pellicle. 

Fermi's, Cohn's, and Uschinsky's solu- 
tions: Good growth. 

Hydrogen sulfide not produced. 

Indole not produced. 

Nitrites produced from nitrates. 

Litmus milk: Unchanged after 2 weeks. 

Acid but no gas from glucose, galactose, 
fructose, arabinose, xylose, lactose, sucrose, 
dulcitol, glycerol and mannitol. No acid or 
gas from raffinose. 

Starch: Slight hydrolj'sis. 

Optimum temperature between 25° and 
35° C. 

Source : Four isolates and 4 reisolates from 
leaf spots of orchids by Ark and Thomas. 

Habitat: Pathogenic on Cattleya sp. and 
Phalaenopsis sp. 

138. Pseudomonas dysoxyli Hutchin- 
son, 1949. (New Zealand Jour. Sci. and 
Tech., Sec. B, 30, 1949, 275.) 



dy.so'xy.li. M.L. neut.noun Dysoxylum 
generic name of a forest tree; M.L. gen. noun 
dysoxyli of Dysoxylum. 

Rods 0.4 to 0.6 by 0.6 to 1.0 micron. 
Motile with 1 to 2 polar flagella. Gram-nega- 
tive. 

Gelatin: No liquefaction. 

Beef -peptone agar colonies: Circular, 
punctiform to 8 mm in diameter, gray, 
translucent. Surface smooth and edges en- 
tire to undulate. Medium brown in 1 week. 

Nutrient broth: Dense flocculent pellicle 
at surface. Strong clouding in 3 days. 

Litmus milk: No change in 4 days. After 
12 days amber whey at top and 1 inch of pink 
precipitate at base. 

Indole not produced. 

Hydrogen sulfide not produced. 

Methyl red test negative; acetylmethyl- 
carbinol not produced. 

Nitrites not produced from nitrates. 

Synthetic medium: Acid but no gas from 
glucose, fructose, lactose, sucrose, raffinose 
and mannitol within 3 weeks. No acid from 
arabinose, maltose, melizitose, starch, 
inulin, dextrin, glycerol or salicin. 

Starch hydrolj^zed. 

Temperature relations: Optimum, 25° C. 
Minimum, 4° C. Maximum, 36° C. 

Source: Many cultures isolated from 
diseased leaves of Dysoxylum spectabile in 
New Zealand. 

Habitat: Pathogenic on leaves of the 
forest tree Dysoxylum spectabile. 

139. Pseudomonas helianthi (Kawa- 
mura, 1934) SSvulescu, 1947. {Bacterium 
helianthi Kawamura, Ann. Phyt. Soc. 
Japan, 4, 1934, 27; Savulescu, Anal. Acad. 
Romane,III,^^, 1947, 11.) 

he.li.an'thi. Gr. heliiis the sun; Gr. 
anthus a flower; M.L. mas. noun Helianthus 
generic name of sunflower; M.L. gen. noun 
helianthi of the sunflower. 

Rods 1.0 to 1.4 by 1.6 to 2.4 microns. 
Motile with a single polar flagellum. Gram- 
negative. 

Gelatin: No liquefaction. 

Beef agar colonies: White, circular, edges 
entire. 

Broth: Turbid. Pellicle. 

Milk: Peptonized. Litmus reduced. 

Nitrates: Gas production. 



FAMILY IV. PSEUDOMONADACEAE 



149 



Indole not produced. 

Hydrogen sulfide not produced. 

Acid but no gas from sucrose and glycerol. 
No acid from lactose and maltose. 

Starch hydrolyzed. 

Temperature relations : Optimum between 
27° and 28° C. Minimum, 12° C. Maximum, 
35.5° C. 

Chemical tolerance: Good growth at pH 
6.4. No growth at pH 5.4 and pH 8.8 

Habitat: Pathogenic on sunflower, Heli- 
anthus debilis. 

140. Pseudonionas melophthora Allen 
and Riker, 1932. (Phytopath., 22, 1932, 557.) 

me.loph'tho.ra. Gr. melum apple; Gr. 
phthora decaj^ destruction; M.L. adj. 
rnelophthonis apple-destroying. 

Rods 0.68 by 1.32 microns. Motile with 2 
polar flagella. Gram-negative; Gram-posi- 
tive cells appear in old cultures. 

Gelatin : No liquefaction. 

Nutrient agar plus 2 per cent glucose: 
Colonies appear in 36 hours. After 3 days 
colonies circular, smooth, glistening, con- 
ve.x; edges entire; light pink, but not con- 
stant. 

Broth: Good growth. Pellicle and sedi- 
ment. 

Milk: Little change, if any. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acid from arabinose, glucose, galactose, 
fructose, sucrose and glycerol. No acid from 
lactose, maltose, dextrin or inulin. 

Starch not hydrolyzed. 

Optimum temperature between 21° and 
25° C. 

Source: Description based on 7 cultures 
isolated from rotting apples and from apple 
maggots. 

Habitat : Pathogenic on apples and found 
with the apple maggot , Rhagoletis ponionella. 

141. Pseudonionas alboprecipitans 

Rosen, 1922. (Ann. Missouri Bot. Garden, 9, 
1922, 383.) 

al.bo.pre.ci'pi.tans. L. album the color 
white; L. v. praecipito to precipitate; M.L. 
part. adj. alboprecipitans forming a white 
sediment. 

Description revised in accordance with 



Johnson, Roberts and Cash (Jour. Agr. Res., 
78, 1949, 723). 

Rods, 0.6 by 1.8 microns, occurring singly 
or in pairs. Encapsulated. Motile with a 
polar flagellum. Gram-negative. 

Gelatin: Liquefied 

Nutrient agar colonies: White, circular, 
raised, smooth, sticky, with margins entire. 
Whitish discoloration of the medium. 

Broth: Turbid in 24 hours. Heavy sedi- 
ment in old cultures. 

Uschinsky's solution: Turbid in 24 hours; 
pellicle formed. 

Cohn's and Fermi's solutions: No growth. 

Milk: Becomes alkaline and slowly clears. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide production slight. 

Acid but no gas from glucose, galactose, 
fructose, sucrose, lactose, raflfinose, glycerol 
and mannitol. No acid from maltose. 

Starch hydrolyzed. 

Temperature relations : Optimum between 
30° and 35° C. Minimum, 0° C. Maximum, 
40° C. 

Aerobic. 

Distinctive character: White precipitate 
in culture media. 

Source: Isolated a number of times from 
foxtail grass. 

Habitat: Pathogenic on foxtail, Chacto- 
chloa hdescens, and other grasses. 

142. Pseudonionas andropogonis (Erw. 
Smith, 1911) Stapp, 1928. (Bacterium andro- 
pogoni (sic) Erw. Smith, Bacteria in Relation 
to Plant Diseases, 2, 1911, 63; Elliott and 
Smith, Jour. Agr. Res., 38, 1929, 4; Pseudo- 
nionas andropogoni (sic) Stapp, in Sorauer, 
Handbuch der Pflanzenkrankheiten, 2, 5 
Aufl., 1928,27.) 

an.dro.po.go'nis. Gr. aner, andris a man; 
Gr. mas. noun pogon, pogonis beard; M.L. 
mas. noun Andropogon, -onis man's beard, 
generic name; M.L. gen. noun andropogonis 
of Andropogon. 

Description from Elliott and Smith (op. 
cit., 1929, 4). 

Rods 0.64 by 1.76 microns. Motile with 
one to several bipolar flagella. Encapsu- 
lated. Gram-negative. 

Gelatin: Feeble liquefaction or none. 

Beef -extract agar colonies : Slow growing, 
round, smooth, glistening, viscid, white. 



150 



ORDER I. PSEUDOMONADALES 



Broth: Growth slow with moderate tur- 
bidity in 48 hours. A thin pellicle. 

Milk: Alkaline and clears. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 3£, 1942,601). 

Acid but no gas from glucose, arabinose, 
fructose and xylose. No acid from sucrose, 
maltose, lactose, raffinose, glycerol or 
mannitol. 

Starch partially digested. 

Temperature relations : Optimum between 
22° and 30° C. Minimum, 1.5° C. Maximum 
between 37° and 38° C. 

Chemical tolerance: Optimum pH be- 
tween 6.0 and 6.6. Minimum, 5.0. Maximum 
between 8.3 and 8.6. 

Source : Elliott used for her description 4 
cultures isolated from lesions on sorgo, 
sorghum and broom-corn. 

Habitat: Pathogenic on sorghum, Holcus 
sorghum. 

143. Pseudomonas lignicola Westerdijk 
and Buisman, 1929. (De lepenziekte, Arn- 
hem, 1929, 51.) 

lig.ni'co.la. L. lignum wood; L. -cola 
dweller; M.L. fem.noun lignicola wood 
dweller or inhabitant. 

Rods. Single or short chains. Motile with 
1 to several polar flagella. Gram-negative. 

Gelatin: No liquefaction. 

Malt agar streaks: Milk-w^hite with a 
colorless edge. 

Broth: Turbid with light pellicle. 

Milk: No coagulation. No acid. 

Nitrites not produced from nitrates. 

Indole not produced. 

Starch hydrolysis slight. 

Optimum temperature, ±25° C. 

Source : From vessels of elm wood showing 
dark discoloration, in Holland. 

Habitat: Pathogenic on elm wood. 

144. Pseudomonas petasitis (Takimoto, 

1927) Siivulescu, 1947. {Bacterium petasitis 
(sic) Takimoto, Ann. Phyt. Soc. Japan, 
2, 1927, 55; Savulescu, Anal. Acad. Romane, 
III,^^, 1947, 11.) 

pe.ta'si.tis. Gr. mas. noun petasus a 
sombrero, a broad-brimmed felt hat; Gr. 



mas. noun petasites a broad-leafed plant, 
colt's foot; M.L. mas. noun Petasites generic 
name; M.L. gen. noun petasitis of Petasites. 

Rods 0.8 to 1.1 by 1.1 to 1.7 microns. 
Motile with a polar flagellum. Gram- 
negative. 

Gelatin: No liquefaction. 

Beef agar colonies: White, circular or 
amoeboid, butyrous. 

Broth: Strong turbidity. Pellicle. 

Milk: Coagulated in 30 days. 

Nitrites produced from nitrates with gas 
formation. 

Indole not produced. 

Hydrogen sulfide not produced. 

No evident acid in peptone broth, but gas 
from glucose, lactose and sucrose. Acid but 
no gas from glycerol. 

Weak growth in broth plus 6 per cent salt. 

Temperature relations : Optimum between 
27° and 30° C. Minimum, approximately 
5° C. Maximum, 47° C. 

Source: Isolated from brown to black 
lesions on Petasites japonicus in Japan. 

Habitat : Pathogenic on leaves of Petasites 
japonicus. 

145. Pseudomonas woodsii (Erw. Smith, 
1911) Stevens, 1925. {Bacterium woodsii 
Erw. Smith, Bacteria in Relation to Plant 
Diseases, 2, 1911, 62; Stevens, Plant Disease 
Fungi, New York, 1925, 39.) 

wood 'si. i. Named for A. F. Woods, an 
American plant pathologist; M.L. gen. noun 
woodsii of Woods. 

Description from Burkholder and Guter- 
man (Phytopath., 25, 1935, 118). 

Rods 0.67 by 1.56 microns. Motile with a 
polar flagellum. Gram-negative. 

Gelatin: No liquefaction. 

Beef -extract agar slants : Growth slow and 
scant, filiform, creamy, butyrous. 

Broth: Turbid. 

Milk: Becomes alkaline but otherwise 
little changed. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 3^, 1942,601). 

Acid but no gas from glucose, fructose, 
galactose, arabinose, xylose, rhamnose, lac- 
tose, glycerol and mannitol. Alkaline reac- 



FAMILY IV. PSEUDOMONADACEAE 



151 



tion from salts of acetic, citric, malic and 
succinic acids. Sucrose, maltose, salicin, and 
lactic and formic acids not fermented. 

Starch not hydrol3-zed. 

Slight growth in broth plus 3 per cent salt. 

Aerobic. 

Source: Isolated from water-soaked 
lesions on carnation leaves. 

Habitat: Pathogenic on carnation, Dian- 
tfius canjophylbis. 

146. Pseudonionas eriobotryae (Taki- 
moto, 1931) Dowson, 1943. {Bacterium erio- 
botryae Takimoto, Jour. Plant Protect., 18, 
1931, 354; Dowson, Trans. Brit. Mycol. Soc, 
26, 1943, 10.) 

e.ri.o.bo'trj^.ae. Gr. erium wool; Gr. 
hotrys grape cluster; M.L. fem.noun Erioho- 
trya woolly grape, a generic name; M.L. 
gen. noun eriobotryae of Eriobotrya. 

Translated by Dr. K. Togashi. 

Rods 0.7 to 0.9 by 2.2 to 3.0 microns. 
Motile, with 1 or 2 flagella. Gram-negative. 

Gelatin: Not liquefied. 

Agar-plates : Colonies appear after 3 days, 
white or hyaline, butyrous, margins entire. 

Broth: Moderately turbid; pellicle pow- 
dery; ring formed. 

Milk: No coagulation, peptonized slowly. 
Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

No acid or gas from glucose, sucrose, lac- 
tose or glycerol in broth. 

Starch not hj^lrolyzed. 

Temperature relations : Optimum between 
25° and 26° C. Minimum, below 4° C. Maxi- 
mum, 32° C. Thermal death point, 51° C. 

Aerobic. 

Source: Species isolated from loquat, 
Eiiobotrya japonica. 

Habitat: Causes a bud rot of Eriobotrya 
japonica. 

147. Pseudonionas panicimiliacei 

(Ikata and Yamauchi, 1931) SSvulescu, 
1947. {Bacterium panici-miliacei Ikata and 
Yamauchi, Jour. Plant Protect., 18, 1931, 
35; Pseudomonas panici-miliacei (sic) Siivu- 
lescu. Anal. Acad. Romane, III, 22, 1947, 
11.) 
pa.ni.ci.mi.li.a'ce.i. L. panicum panic 



grass; L. adj. miliaceus pertaining to millet; 
Panicum miliaceum millet. 

Description translated by Dr. K. Togashi. 

Rods 0.8 to 1.1 by 1.8 to 2.6 microns. 
Motile, with a single flagellum. Gram- 
negative. 

Gelatin: Not liquefied. 

Potato-agar plates: Growth moderate, 
whitish, then tinged with light orange, un- 
dulating margins. 

Broth: Turbid; white pellicle formed. 

Milk: No coagulation and slow digestion. 
Alkaline. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

No acid and no gas from sucrose, glucose, 
lactose, glycerol or sodium nitrate. 

Starch not hydroh'zed. 

Optimum temperature between 30° and 
35° C. 

Aerobic, facultative. 

Source : Species first isolated from millet, 
Panicum, miliaceum. 

Habitat: Causes a leaf stripe of Panicum 
miliaceum. 

148. Pseudonionas saliciperda Lin- 

deijer, 1932. (Inaug. Diss., Univ. Amster- 
dam, 1932; Phytopath. Ztschr., 6, 1933, 373.) 

sa.li.ci.per'da. L. salix, salicis willow; L. 
perdo to destroy; M.L. fem.noun saliciperda 
willow^ destroyer. 

Rods 1.2 to 2.1 microns in length. Motile 
with a polar flagellum. Gram-negative. 

Gelatin: No liquefaction. 

Beef wort agar colonies: Gray-white. 

Milk: No acid nor coagulation. 

Nitrites produced (small amount) from 
nitrates. 

Indole production slight. 

No gas from carbohydrates. 

Starch not hydrolyzed. 

Aerobic, facultative. 

Source: Isolated from wilted branches of 
willow. 

Habitat: Pathogenic on willow, Salix spp. 

149. Pseudomonas wieringae (Elliott, 
1930) Savulescu, 1947. {Phytomonas betae 
Wieringa, Nederl. Tijdschr. Hyg., Micro- 
biol, en Serol., Leiden, 2, 1927, 148; Bac- 



152 ORDER I. PSEUDOMONADALES 

terium wieringae Elliott, Man. Bact. Plant Rods 0.5 by 2.0 microns. Motile with 1 to 

Pathogens, 1930, 264; Saviilescu, Anal. 5 polar flagella. Gram-negative. 

Acad. Romane, III, 22, 1947, 11.) Beef -agar colonies: Smooth, round, white 

wie'ring.ae. Named for Dr. K. T. Wie- to grayish, fluorescent, 

ringa, the bacteriologist who first described Milk: Cleared in 5 days. Not coagulated, 

the species; M.L. gen. noun wieringae of Nitrites not produced from nitrates. 

Wieringa. No gas from sugars. 

Because Bacterium betae Chester (Ann. Temperature relations : Optimum between 

Rept. Del. Col. Agr. Exp. Sta., 9, 1897, 53) 28° and 30° C. Minimum, 4° C. Maximum, 

may be a pseudomonad, the more distinctive 37° C. 

species name proposed by Elliott has been Source: Isolated from vascular rot of 

retained. beets in Holland. 

Description from Elliott (op. cit., 1930, Habitat: Pathogenic on beets, Beta vul- 

264). garis. 

Genus II. Xanthomonas Dowson, 1939 * 

{Phijtomonas Bergey et al., Manual, 1st ed., 1923, 174; not Phytomonas Donovan, Lancet, 

177, 1909, 1495 (type species (monotypy) Phytomonas davidi Donovan, a flagellate); 

Dowson, Zent. f. Bakt., II Abt., 100, 1939, 187.) 

Xan.tho'mo.nas or Xan.tho.mo'nasf. Gr. adj. xanthus yellow; Gr. fem.n. monas unit, 
monad; M.L. fem.n. Xanthomonas yellow monad. 

Cells usually monotrichous. A yellow, non-water-soluble pigment is produced on agar. A 
diffusible, brown color infrequently occurs in beef extract agar. Proteins are usually readily 
digested. Milk usually becomes alkaline. Hydrogen sulfide is produced. Asparagine is not 
sufficient as an only source of carbon and nitrogen. Acid (and also gas in one species, No. 
19) produced from mono- and disaccharides. Some species liquefy a pectin medium, others 
do not (Burkholder and Starr, Phytopath., 38, 1948, 500). Mostly plant pathogens causing 
necroses. 

The type species is Xanthomonas hyacinthi (Wakker) Dowson. 

Key to the species of genus Xanthomonas. 

I. Colonies yellow; pigment non -water-soluble. 
A. Gelatin liquefied. 

1. Starch hydrolysis feeble. 

a. Nitrites not produced from nitrates. 

1. Xanthomonas hyacinthi. 

2. Xanthomonas pruni. 

3. Xanthomonas vitians. 
aa. Nitrites produced from nitrates. 

4. Xanthomonas beticola. 

5. Xanthomonas rubrilineans . 

2. Starch hydrolysis strong. 

a. Nitrites not produced from nitrates. 

b. No brown pigment in beef -extract agar. 

6. Xanthomonas barbareae. 

7. Xanthomonas begoniae. 

8. Xanthomonas betlicola. 

9. Xanthomonas campestris. 

* Prepared by Prof. Walter H. Burkholder, Cornell University, Ithaca, N. Y., June, 
1943; revised November, 1953. 
t The former accords with the Latin rules of accentuation; the latter is in common usage. 



FAMILY IV. PSEUDOMONADACEAE 153 

10. Xanthomonas cassiae. 

11. Xanthomonas cajani. 

12. Xanthomonas citri. 

13. Xanthomonas derodendri. 

14. Xanthomonas corylina. 

15. Xanthomonas cucurbitae. 

16. Xanthomonas desmodii. 

17. Xanthomonas desmodiigangeticii. 

18. Xanthomonas dieffenbachiae . 

19. Xanthomonas hemmiana. 

20. Xanthomonas holcicola. 

21. Xanthomonas incanae. 

22. Xanthomonas juglandis. 

23. Xanthomonas lespedezae. 

24. Xanthomonas macidifolngardeniae. 

25. Xanthomonas malvacearum. 

26. Xanthomonas pelargonii. 

27. Xanthomonas phaseoli. 

28. Xanthomonas plantaginis . 

29. Xanthomonas ricinicola. 

30. Xanthomonas sesbaniae. 

31. Xanthomonas stizolobiicola. 

32. Xanthomonas taraxaci. 

33. Xanthomonas translucens. 

34. Xanthomonas uppalii. 

35. Xanthomonas vasculorum. 

36. Xanthomonas vesicatoria. 

37. Xanthomonas vignicola. 
bb. Brown pigment produced in beef-extract media. 

38. Xanthomonas nakatae. 
27. Xanthomonas phaseoli. 

aa. Nitrites produced from nitrates. 

39. Xanthomonas papavericola. 
aaa. Ammonia produced from nitrates. 

40. Xanthomonas alfalfae. 

3. Starch not hydrolyzed. 

a. Nitrites produced from nitrates. 

41. Xanthomonas acernea. 
aa. Nitrites not produced from nitrates. 

42. Xanthomonas carotae. 

43. Xanthomonas hederae. 

44. Xanthomonas phormicola. 
36. Xanthomonas vesicatoria. 

aaa. Ammonia produced in nitrate media. 

45. Xanthomonas geranii. 

4. Starch hydrolysis not reported. 

a. Nitrites produced from nitrates. 

46. Xanthomonas antirrhini. 

47. Xanthomonas heterocea. 
aa. Nitrites not produced from nitrates. 

48. Xanthomonas badrii. 

49. Xanthomonas gummisudans. 

50. Xanthomonas nigromacidans. 



154 ORDER I. PSEUDOMONADALES 



B. Gelatin not liquefied. 

1. Starch hydrolyzed. 

2. Starch not hydrolyzed. 

C. Gelatin not reported. 
1. Starch hydrolyzed. 



51. Xanthomonas axonopodis. 

52. Xanthomonas oryzae. 



53. Xanthomonas celebensis. 
II. Colonies whitish to cream; pigment non-water-soluble. 

A. Gelatin liquefied. 
1. Starch hydrolyzed. 

a. Nitrites produced from nitrates. 

54. Xanthomonas panici. 



aa. Nitrites not reported. 
2. Starch not reported. 



55. Xanthomonas proteamaculans . 

56. Xanthomonas manihotis . 

57. Xanthomonas ruhrisuhalhicans 

58. Xanthomonas cannae. 

59. Xanthomonas conjac. 

60. Xanthomonas zingiberi. 



HOST PLANT KEY 

The following key will be found useful for purposes of identification where the bacterium 
is isolated from a known host plant. 

I. Cause of leaf, stem and fruit spots and occasional blights of monocotyledonous plants. 

A. Attack members of the family Araceae. 

59. Xanthomonas conjac. 

18. Xanthomonas dieffenbachiae. 

B. Attacks members of the family Cannaceae. 

58. Xarithomonas cannae. 

C. Attack members of the family Gramineae. 

51. Xanthomonas axonopodis. 
20. Xanthomonas holcicola. 

52. Xanthomonas oryzae. 

53. Xanthomonas panici. 

5. Xanthomonas rubrilineans . 
57. Xanthomonas rubrisubalbicans . 
33. Xanthomonas translucens. 
35. Xanthomonas vasculorum,. 

D. Attacks members of the family Iridaceae. 

49. Xanthomonas gummisudans. 

E. Attack members of the family Liliaceae. 

1. Xanthomonas hyacinthi. 
44. Xanthomonas phormicola. 

F. Attacks members of the family Musaceae. 

52. Xanthomonas celebensis. 

G. Attacks members of the family Zingiberaceae. 

60. Xanthomonas zingiberi. 

II. Cause of leaf, stem and fruit spots and occasional blights of dicotyledonous plants. 
A. Attacks members of the family Aceraceae. 

41. Xanthomonas acernea. 



FAMILY IV. PSEUDOMONADACEAE 155 

B. Attacks members of the family Araliaceae. 

43. Xanlhomonas hederae. 

C. Attacks members of the family Bcgoniaceae. 

7. Xanthovwnas begomae. 

D. Attacks members of the family Befulaceae. 

14. Xanthomonas corylina. 

E. Attacks members of the family Chenopodiaceae. 

4. Xanthomonas beticola. 

F. Attack members of the family Compositae. 

48. Xanthomonas hadrii. 
50. Xanthomonas nigromaculans. 
32. Xanthomonas taraxaci. 
3. Xanthomonas vitians. 

G. Attacks members of the family Convolvulaceae. 

34. Xanthomonas uppalii. 
H. Attack members of the family Cruciferae. 

6. Xanthomonas barbareae. 
9. Xanthomonas campestris. 

21. Xanthomonas incanae. 

36. Xanthomonas vesicatoria. 
I. Attacks members of the family Cucurbitaceae. 

15. Xanthomonas cucurbitae. 
J. Attack members of the family Euphorbiaceae. 

56. Xanthomonas manihotis. 

29. Xanthomonas ricinicola. 
K. Attack members of the family Geraniaceae. 

45. Xanthomonas geranii. 

26. Xanthomonas pelargonii. 
L. Attacks members of the family Jnglandaceae. 

22. Xanthomonas juglandis. 
M. Attack members of the family Leguminosae. 

40. Xanthomonas alfalfae. 
11. Xanthomonas cajani. 
10. Xanthomonas cassiae. 

16. Xanthomonas desmodii. 

17. Xanthomonas desmodiigangeticii . 

23. Xanthomonas lespedezae. 

27. Xanthomonas phaseoU. 

30. Xanthomonas sesbaniae. 

31. Xanthomonas stizolobiicola. 

37. Xanthomonas vignicola. 
N. Attacks members of the family Malvaceae. 

25. Xanthomonas malvacearum. 
O. Attacks members of the family Papaveraceae. 

39. Xanthomonas papavericola. 
P. Attacks members of the family Piper aceae. 

8. Xanthomonas betUcola. 
Q. Attacks members of the family Plantaginaceae . 

28. Xanthomonas plantaginis. 
R. Attacks members of the family Proteaceae. 

55. Xanthomonas proteamaculans . 
S. Attacks members of the family Rosaceae. 

2. Xanthomonas pruni. 



156 



ORDER I. PSEUDOMONADALES 



T. Attacks members of the family Rubiaceae. 

24. Xanthomonas maculifoliigardeniae. 
U. Attacks members of the family Rutaceae. 

12. Xanthomonas citri. 
V. Attacks members of the family Scrophulariaceae. 

46. Xanthomonas antirrhini. 
W. Attack members of the family Solanaceae. 

19. Xanthomonas hemmiana. 

47. Xanthomonas heterocea. 
36. Xanthomonas vesicatoria. 

X. Attacks members of the family Tiliaceae. 

38. Xanthomonas nakatae. 
Y. Attacks members of the family Umbelliferae. 

42. Xanthomonas carotae. 
Z. Attacks members of the family Verbenaceae. 

13. Xanthomonas clerodendri . 



1. Xanthomonas hyacinth! (Wakker, 
1883) Dowson, 1939. {Bacterium hyacinthi 
Wakker, Botan. Centralblatt, 14, 1883, 315; 
Dowson, Zent. f. Bakt., II Abt., 100, 1939, 
188.) 

hy.a.cin' thi. Gr. hyacinthus the hyacinth; 
M.L. mas.n. Hyacinthus generic name; M. 
L. gen. noun hyacinthi of hyacinth. 

Description from Smith (Div. Veg. Phys. 
and Path., U. S. D. A. Bui. 26, 1901, 40); 
additional characters determined by Burk- 
holder. 

Rods 0.4 to 0.6 by 0.8 to 2.0 microns. 
Motile with a polar flagellum. Filaments 
present. Gram-negative. 

Gelatin: Slow liquefaction. 

Agar colonies: Circular, flat, moist, 
shining, bright yellow. Media stained 
brown. 

Milk: Casein is precipitated and digested. 
Tyrosine crystals produced. 

Nitrites not produced from nitrates. 

Indole: Slight production. 

Hydrogen sulfide produced. 

Acid but no gas from glucose, fructose, 
lactose, sucrose, galactose, maltose, salicin 
and ethyl alcohol. Slight acid from xylose. 
Alkaline reaction in citrate. Mannitol, 
dulcitol and malonate not utilized. 

Starch: Hydrolysis slight. 

Pectate medium not liquefied. 

Temperature relations: Optimum, be- 
tween 28° and 30° C. Minimum, 4° C. Ma.xi- 
mum, between 34° and 35° C. 

Aerobic, with the exception of maltose, 
where it is facultatively anaerobic. 



Habitat: Produces a yellow rot of hj-a- 
cinth bulbs, Hyacinthus ovientalis. 

2. Xanthomonas pruni (Erw. Smith, 
1903) Dowson, 1939. {Pseudomonas pruni 
Erw. Smith, Science, N. S. 17, 1903, 456; 
Dowson, Zent. f. Bakt., II Abt., 100, 1939, 
190.) 

pru'ni. L. prunus plum; M.L. fem.n. 
Prunus generic name; M.L. gen. noun 
pruni of Prunus. 

Description from Dunegan (U. S. Dept. 
Agr., Tech. Bull. 273, 1932, 23). 

Rods 0.2 to 0.4 by 0.8 to 1.0 micron. 
Encapsulated. INIotile with a polar flagellum. 
Gram-negative. 

Gelatin: Liquefied. 

Beef -extract agar colonies: Yellow, circu- 
lar, smooth, convex, edges entire. 

Broth: Turbid becoming viscid. 

Milk: Precipitation of casein; digestion. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. Hydrogen 
sulfide produced (Burkholder). 

Lipolytic (Starr and Burkholder, Phj^- 
topath., 32, 1942, 600). 

Acid from arabinose, .xylose, glucose, 
fructose, galactose, manno.se, maltose, lac- 
tose, sucrose, rafRnose and melezitose. 

Starch is hydrolyzed (slight). 

Pectate medium not liquefied. 

Aerobic. 

Temperature relations: Optimum, be- 
tween 24° and 29° C. Maximum, 37° C. 



FAMILY IV. PSEUDOMONADACEAE 



157 



Source: Smith isolated this ])uthogeii from 
Japanese plimis. 

Habitat: Pathogenic on plum {Prunus 
salicina), peach (P. persica), apricot (P. 
(irmeniaca), etc. 

3. Xaiilhonionas vilians (Brown, 1918) 
Dowson, 1943. {Bacterium vitians Brown, 
Jour. Agr. Res., 13, 1918, 379; Dowson, 
Trans. Brit. Mycol. Soc, 26, 1943, 13.) 

vi'ti.ans. L. vitio to injure; L. part. adj. 
vitians injuring. 

Rods. Motile with bipolar flagella. Gram- 
negative. 

Gelatin: Slow liquefaction. 

Beef-extract agar colonies: Circular, 
smooth, thin, cream to cream-yellow. 

Broth: Turbid with yellow ring. 

Milk: Clears and turns alkaline. 

Nitrites not produced from nitrates. 

Indole: Feeble production. 

Hydrogen sulfide: Feeble production. 

Acid but no gas from glucose. 

Starch: Feeble hydrolysis. 

Pectate medium not liquefied. 

Temperature relations: Optimum, be- 
tween 26° and 28° C. Minimum, 0° C. Maxi- 
mum, 35° C. 

Aerobic. 

Source : Isolated from the stem of diseased 
lettuce plants from South Carolina. 

Habitat: Pathogenic on lettuce, Lactuca 
sativa. 

4. Xanthonionas beticola (Smith 
et al., 1911) Savulescu, 1947. {Bacterium 
beticolum Smith, Brown and Townsend, U. 
S. Dept. Agr., Bur. Plant Ind., Bui. 213, 
1911, 194; S&vulescu, Anal. Acad. Romane, 
III, 22, 1947, 12). 

be.ti'co.la. L. beta the beet; L. v. colo to 
inhabit; M.L. noun beticola the beet dweller. 

Description from Brown, Jour. Agr. Res., 
37, 1928, 167, where the species is referred to 
as Bacterium beticola (Smith, Brown and 
Townsend) Potebnia. 

Rods 0.4 to 0.8 by 0.6 to 2.0 microns. 
Motile with 1 to 4 polar flagella. Encapsu- 
lated. Presumably Gram-negative although 
originally reported as Gram-variable. 

Gelatin: Liquefied. 

Beef-agar slants: Growth moderate, 
filiform, flat, glistening, yellow. 



Broth: Turbid, yellow ring, abundant 
sediment. 

Milk: Coagulation and peptonization. 

Indole not produced. 

Hydrogen sulfide produced. 

Nitrites produced from nitrates. 

Acid from glucose, sucrose, maltose and 
mannitol. No acid from lactose. 

Starch hydrolysis feeble. 

Temperature relations: Optimum, 29° C. 
Minimum, 1.5° C. Maximum, 39° C. 

Chemical tolerance: Optimum pH, 6.5. 
Minimum, between 4.5 and 4.8. Maximum, 
between 9.0 and 9.5. 

Tolerates salt up to 9 per cent. 

Aerobic. 

Comment: It is doubtful whether this 
species belongs in this genus. 

Source: Isolated from galls on sugar beets 
collected in Colorado, Kansas and Virginia. 

Habitat: Produces galls on sugar beets 
and on garden beets. 

5. Xanthomonas rubrilineans (Lee et 
al., 1925) Starr and Burkholder, 1942. 
{Phytomonas rubrilineans Lee, Purdy, Bar- 
num and Martin, Hawaiian Sugar Planters' 
Assoc. Bui., 1925, 25; Starr and Burkholder, 
Phytopath., 32, 1942, 600.) 

ru.bri.li'ne.ans. L. ruber red; lineo to 
make a straight line; rubrilineans making 
red stripes. 

Rods 0.7 by 1.67 microns. Motile with 1 
or seldom more polar flagella. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Agar (Beef-extract + glucose) colonies: 
Small, smooth, glistening, buff to yellow. 

Broth: Turbid with pellicle. Sediment. 

Milk: Casein precipitated and digested. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 32, 1942, 600). 

Acid from glucose, fructose, arabinose, 
xylose, lactose, sucrose, raffinose and man- 
nitol. 

Starch: Slight hydrolysis. 

Pectate medium not liquefied. 

Growth range, pH 5.4 to pH 7.3. 

Aerobic, facultative. 



158 



ORDER I. PSEUDOMONADALES 



Source: Isolated from red stripe lesions in 
sugar cane. 

Habitat: Pathogenic on sugar cane. 

6. Xanthoinonas barbareae Burkholder, 
1941. (Phytopath., 31, 1941, 348.) 

bar.ba're.ae. M.L. fem.n. Barbarea ge- 
neric name of cress; M.L. gen. noun barbareae 
of Barbarea. 

Rods 0.4 to 0.95 by 1.0 to 3.15 microns. 
Motile with a single polar flagellum. Gram- 
negative. 

Gelatin: Liquefied. 

Beef-extract peptone colonies: Circular, 
yellow, smooth, butyrous, growth moderate. 

Potato glucose agar: Growth abundant, 
pale 3'ellow. Mucoid. 

Broth: Turbid, j^ellow granular ring. 

Milk: Soft curd, with clearing and produc- 
tion of tyrosine crystals. Litmus reduced. 

Nitrates utilized but no nitrites produced. 
Asparagine and nitrites not utilized. 

Hydrogen sulfide produced. 

Indole not produced. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

Acid from glucose, galactose, xylose, 
maltose, sucrose and glycerol. Alkali pro- 
duced from salts of malonic, citric, malic 
and succinic acids. Rhamnose, salicin and 
hippuric acid salts not utilized. 

Starch hydrolyzed. 

Pectate medium liquefied. 

Aerobic. 

Distinctive characters: Similar to 
Xanthomonas campestris but does not infect 
cabbage, cauliflower or horseradish. 

Source: From black rot of winter cress, 
Barbarea vulgaris. 

Habitat: Pathogenic on leaves and stems 
of Barbarea vulgaris. 

7. Xanthoinonas begoniae (Takimoto, 
1934) Dowson, 1939. (Bacterium begoniae 
Takimoto, Jour. Plant Protect., 21, 1934, 
262; Dowson, Zent. f. Bakt., II Abt., 100, 
1939, 190.) 

be.go'ni.ae. Named for B6gon; M.L. 
fem.n. Begonia generic name; M.L. gen. 
noun begoniae of Begonia. 

Translated by Dr. K. Togashi. 

Rods 0.5 to 0.6 by 1.2 to 2.0 microns. 



Motile with a polar flagellum. Gram- 
negative. 

Gelatin: No liquefaction. Liquefaction 
(Wieringa, Tidschr. Plantziekt., 4I, 1935, 
312; McCulloch, Jour. Agr. Res., 54, 1937, 
859; Dowson, op. cit., 1939, 190; Stapp, 
Arbeiten Biol. Reichsanst. f. Land- u. 
Forstw., 22, 1938, 392). 

Potato agar colonies: Circular, convex, 
smooth, moist, shining, yellow. 

Broth: Turbid. Yellow pellicle and pre- 
cipitation. 

Milk: No coagulation. Casein digested. 
Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

No acid or gas in peptone broth from 
glucose, sucrose, lactose or glycerol. Acid 
from glucose, sucrose, lactose, mannitol and 
glycerol in peptone-free medium (McCul- 
loch, op. cit., 1937,859). 

Starch hydrolyzed (Dowson, Jour. Roy. 
Hort. Soc.,6S, 1938,289). 

Pectate medium not liquefied. 

Temperature relations: Optimum, 27°C. 
Minimum, between 1° and 3° C. Maximum, 
37° C. 

Source: Isolated from leaf spot of tu- 
berous begonia. 

Habitat: Pathogenic on Begonia spp. 

8. Xanthomonas betlicola Patel et al., 
1951. (Patel, Kulkarni and Dhande, Curr. 
Sci.,^0, 1951, 106.) 

bet.li'co.la. East Indian betle, the name 
of the betel, a shrubby vine; L. v. colo to 
dwell; M.L. fem.n. betlicola the betel- 
dweller. 

Rods slender, occurring singly or in 
pairs. Motile. Encapsulated. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Potato-glucose agar colonies: 11 mm in 
diameter in 7 days, baryta-yellow, lobate, 
striations at periphery. 

Broth: Turbid; yellow growth. 

Milk: Litmus reduced. Casein digested. 

Loeffler's blood serum liquefied. 

Indole not produced. 

Hydrogen sulfide produced. 



FAMILY IV. PSEUDOMONADACEAE 



159 



Nitrites not produced from nitrates. 

Methyl red negative: acetylmethylcarbi- 
nol not produced. 

Synthetic asparagine medium: No growth. 

Acid but no gas from glucose, lactose and 
sucrose. Salicin not attacked. 

Starch hydrolyzed. 

Salt tolerance: Up to 3 per cent. 

Optimum temperature, between 25° and 
28° C. 

Aerobic. 

Source: Isolated from leaves, stems and 
petioles of Piper betle in India. 

Habitat: Pathogenic on Piper betle. 



Aerobic. 

Distinctive characters : Causes a vascular 
infection in cabbage, cauliflower and ruta- 
bagas. 

Comment : A variety pathogenic on horse- 
radish and related species has been de- 
scribed by McCulloch (Jour. Agr. Res., 38, 
1929, 269). Causes a leaf spot. Does not 
liquefy pectate medium. 

Source: Pammel {op. cit., 1895, 130) first 
isolated the pathogen from diseased ruta- 
bagas. 

Habitat: Pathogenic on cabbage, cauli- 
flower and other related species. 



9. Xanthoiuonas campestris (Pammel, 
1895) Dowson, 1939. (Bacillus campestris 
Pammel, Iowa Agr. Exp. Sta. Bull. 27, 
1895, 130; Dowson, Zent. f. Bakt., II Abt., 
100, 1939, 190.) 

cam.pes'tris. L. campestris of a level 
field this specific epithet is also that of 
Brassica campestris , a host. 

Description from McCulloch (Jour. Agr. 
Res., 38, 1929, 278). Species is probably 
composed of several varieties. See descrip- 
tions by Mekta, Ann. Appl. Biol., 12, 1925, 
330; Paine and Nirula, Ann. Appl. Biol., 
15, 1928, 46; Wormald and Frampton, Ann. 
Rept. East. Mall. Res. Sta., 1926 and 1927, 
II Supplement, 1928, 108; and others. 

Rods 0.3 to 0.5 by 0.7 to 2.0 microns. 
Motile with a polar flagellum. Encapsu- 
lated. Gram-negative. 

Gelatin: Liquefied. 

Beef agar colonies: Wax-j'ellow, round, 
smooth, shining, translucent, margins 
entire. 

Broth: Turbid with yellow rim and some- 
times a pellicle. 

Milk: Casein digested with the formation 
of tyrosine crystals. Alkaline. 

Nitrites not produced from nitrates. 

Indole production weak. 

Hydrogen sulfide produced. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

Acid but no gas from glucose, sucrose, 
lactose, glycerol and mannitol. 

Starch hydrolyzed. 

Pectate medium liquefied. 

Temperature relations: Optimum, be- 
tween 28° and 30° C. Maximum, 36° C. 



10. Xanthonionas cassiae Kulkarni et 
al., 1951. (Kulkarni, Patel and Dhande, 
Curr. Sci., 20, 1951, 47.) 

cas'si.ae. M.L. fem.n. Cassia generic name 
of host; M.L. gen. noun cassiae of Cassia. 

Rods 0.8 to 1.0 by 1.2 to 2.1 microns. 
Motile with a single polar flagellum. Gram- 
negative. 

Gelatin: Liquefied. 

Potato-glucose agar colonies: 1.2 cm in 
diameter after 7 days, smooth, circular, 
lobate, glistening, convex, butyrous, pinard- 
yellow. 

Milk: Litmus reduced. Medium pepto- 
nized. 

Hydrogen sulfide produced. 

Nitrites not produced from nitrates. 

Loeffler's blood serum: Liquefied. 

Methyl red negative; acetylmethylcar- 
binol not produced. 

Acid but no gas from glucose, lactose and 
sucrose. Arabinose, glycerol and salicin not 
attacked. 

Starch hydrolyzed. 

Koser's citrate medium: Growth. 

Synthetic asparagine medium: Slight 
growth. 

Non-lipolytic. 

Salt tolerance: Up to 3 per cent. 

Optimum temperature, 27° C. 

Aerobic. 

Source: Isolated from leaves, stems and 
petioles of Cassia tora in India. 

Habitat: Pathogenic on Cassia tora. 

11. Xanthonionas cajani Kulkarni et 
al., 1950. (Kulkarni, Patel and Abhyankar, 
Curr. Sci., 19, 1950, 384.) 



160 



PSEUDOMONADALES 



ca'ja.ni. M.L. mas.n. Cajanus generic 
name of host; M.L. gen. noun cajani of 
Cajanus. 

Rods 0.9 to 1.4 by 1.3 to 2.2 microns. 
Encapsulated. Motile with a single polar 
flagellum. Gram-negative. 

Gelatin: Liquefied. 

Potato-glucose agar colonies: 1.5 cm in 
diameter after 7 days, smooth, glistening, 
entire, pulvinate, naphthalene-yellow. 

Milk: Litmus reduced. Casein digested. 

Loeffler's blood serum: Liquefied in 10 
days. 

Hydrogen sulfide produced. 

Nitrites not produced from nitrates. 

Acid but no gas from glucose, lactose and 
sucrose. Salicin not attacked. Citrates 
utilized. 

Starch hydrolyzed. 

Methyl red negative; acetylmethylcar- 
binol not produced. 

Synthetic asparagine medium: No growth. 

Salt tolerance: Up to 3 per cent. 

Optimum temperature, 30° C. 

Aerobic. 

Relationship to other species: Similar to 
Xanthomonas phaseoli, which also infects 
various legumes. 

Source: Isolated from the pigeon pea, 
Cajanus cajan, in India. 

Habitat: Pathogenic on Cajanus cajan. 

12. Xanthomonas citri (Hasse, 1915) 
Dowson, 1939. {Pseudomonas citri Hasse, 
Jour. Agr. Res., 4, 1915, 97; Dowson, Zent. f. 
Bakt., II Abt., 100, 1939, 190.) 

cit'ri. L. citrus the citrus; M.L. fem.n. 
Citrus generic name; M.L. gen. noun citri of 
Citrus. 

Rods, 0.5 to 0.75 by 1.5 to 2.0 microns, 
occurring in chains. Motile with a single 
polar flagellum. Gram-negative. 

Gelatin: Liquefied. 

Beef agar colonies: Appear in 36 to 48 
hours; circular, smooth, raised, dull yellow. 

Broth: Turbid in 24 hours. A yellow ring 
forms. 

Milk: Casein is precipitated. 

Nitrites not produced from nitrates. 

Hydrogen sulfide produced (Reid, New 
Zealand Jour. Sci. and Tech., 22, 1938, 60). 

Indole not produced. 

No gas from glucose, lactose or mannitol. 



Starch hydrolyzed (Reid, loc. cit.). 

Aerobic. 

Temperature relations: Optimum, be- 
tween 25° and 34° C. Minimum, 10° C. 
Maximum, 38° C. (Okabe, Jour. Soc. Trop. 
Agr., J^, 1932,476). 

Source: Isolated from canker on orange. 

Habitat: Produces a canker on man.y 
species of Citrus and related plants. 

13. Xanthomonas clerodendri Patel 
et al., 1952. (Xanthomonas clerodendroni (sic) 
Patel, Kulkarni and Dhande, Curr. Sci., 21, 
1952, 74.) 

cle.ro. den'dri. M.L. neut.n. Clerodendron 
generic name of the plant host; M.L. gen. 
noun clerodendri of Clerodendron. 

Rods, 0.5 by 1.1 microns, occurring singly 
or in chains. Encapsulated. Gram-negative. 

Gelatin: Liquefied. 

Potato-glucose agar colonies: Circular, 
1.8 cm in diameter in 7 days, margins entire. 
Pale lemon-yellow. 

Litmus milk: Casein digested. Litmus re- 
duced and milk peptonized. 

Hydrogen sulfide produced. 

Nitrites not produced from nitrates. 

Acid but no gas from glucose, sucrose and 
lactose. No growth in salicin. 

Starch h3^drolyzed. 

Optimum temperature, about 31° C. 
Thermal death point, 51° C. 

Source: From a leaf spot on Clerodendron 
phlornoides . 

Habitat: Pathogenic on Clerodendron 
phlomoides. 

14. Xanthomonas corylina (Miller et 
al., 1940) Starr and Burkholder, 1942. (Mil- 
ler, Bollen, Simmons, Gross and Barss, 
Phytopath., 30, 1940, 731; Starr and Burk- 
holder, Phytopath., 32, 1942, 598.) 

co.ry.li'na. Gr. conjlus the hazel; IVI.L. 
adj. corylinus pertaining to hazel. 

Rods 0.5 to 0.7 by 1.1 to 3.8 microns. 

Motile with a polar flagellum. Encapsu- 
lated. Gram-negative. 

Gelatin: Liquefied. 

Nutrient glucose-agar streaks: Growth 
abundant, filiform, convex, glistening, 
smooth, opaque, pale lemon-j^ellow, viscid. 

Broth: Turbid. Ring formed in 2 to 5 
days. 

Milk: Enzymatic curd that is slowly di- 



FAMILY IV. PSEUDOMONADACEAE 



161 



gested. Litmus reduced. Crystal formation 
(Burkholder). 

Nitrites not produced from nitrates. 

Nitrogen sources utilized are peptone, 
aspartic acid, alanine, leucine, sodium 
ammonium phosphate, allantoin, t.yrosine, 
uric acid and brucine. 

Indole not produced. 

Hydrogen sulfide not produced on lead 
acetate agar. HoS produced after ZoBell 
and Feltham's method (Burkholder). 

Selenium dioxide reduced. 

Lipolytic (Starr and Burkholder, ibid., 
600). 

Acid but no gas from glucose, fructose, 
galactose, lactose, sucrose, maltose, xylose, 
raffinose, mannitol, glycerol and starch. 
Alkali from salts of citric, lactic, malic and 
succinic acids. Arabinose, rhamnose, dulci- 
tol, salicin, inulin and cellulose not utilized. 

Starch hydrolj^zed. 

Pectate medium not liquefied. 

Temperature relations: Optimum, be- 
tween 28° and 32° C. Minimum, between 5° 
and 7° C. Maximum, 37° C. Thermal death 
point between 53° and 55° C. 

pH range for growth: pH 5.2 to 10.5. Opti- 
mum pH, between 6 and 8. 

Strict aerobe. 

Distinctive characters: Cultural charac- 
ters the same or similar to those of Xantho- 
monas juglandis. The two species do not 
cross-infect. 

Source: 26 isolates from widely scattered 
filbert orchards in Oregon and Washington. 

Habitat: Pathogenic on filberts {Corylus 
avellana and C. maxima). 

15. Xanthomonas cucurbitae (Bryan, 
1926) Dowson, 1939. (Bacterium cucurbitae 
Bryan, Science, 63, 1926, 165; Bryan, Jour. 
Agr. Res., 40, 1930, 389; Dowson, Zent. f. 
Bakt., II Abt., 100, 1939, 190.) 

cu.cur'bi.tae. L. cucurbita a gourd; M.L. 
fem.n. Cucurbita generic name; M.L. gen. 
noun cucurbitae of Cucurbita. 

Rods 0.45 to 0.6 by 0.5 to 1.3 microns. 
Motile, usually with a single polar flagellum. 
Gram-negative. 

Gelatin: Liquefied. 

Beef -agar slants: Growth moderate, mus- 
tard-yellow, undulating margins, viscid to 
butyrous. 



Broth: Moderately turbid. Ring and j-el- 
low sediment. 

Milk: Precipitation of casein; digestion. 
Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

Acid from glucose, galactose, fructose, 
lactose, maltose, sucrose and glycerol. No 
acid from mannitol. 

Starch hydrolyzed. 

Pectate medium not liquefied. 

Temperature relations: Optimum, be- 
tween 25° and 30° C. Maximum, 35° C. 

pH range for growth: pH 5.8 to 9.0. Opti- 
mum pH, between 6.5 and 7.0. 

Slight growth in 5 per cent salt. 

Aerobic. 

Source: Species first isolated from squash. 

Habitat : Causes a leaf spot of squash and 
related plants. 

16. Xanthomonas desniodii Uppal and 
Patel, 1949. (Uppal and Patel, in Patel, 
Curr. Sci., 18, 1949, 213; also see Patel, 
Indian Phytopath., 2, 1949, 5.) 

des.mo'di.i. M.L. neut.n. Desmodium 
generic name of host; M.L. gen. noun 
desmodii of Desmodium. 

Rods, 0.4 to 0.8 by 1.6 to 2.4 microns, oc- 
curring singly or in pairs. Motile with a 
single polar flagellum. Gram-negative. 

Gelatin: Liquefied. 

Nutrient agar slants: Growth fair, filiform, 
flat, dull, smooth, opaque and pinard- 
yellow. 

Potato-glucose agar (neutral) colonies : 
Yellowish amber with colorless margins, 
circular, viscid, smooth and wet. 

Beef broth: Growth slow. Moderate in 48 
hours and good in 4 daj's. 

Milk: Litmus turns red in 10 days. Reduc- 
tion slow. 

Indole not produced. 

Hydrogen sulfide production fair. 

Nitrites not produced from nitrates. 

No growth in Cohn's, Uschinsky's or 
Fermi's solution. 

Acid but no gas from glucose, galactose, 
lactose, mannitol, maltose and sucrose in 
synthetic medium. Poor growth in salicin, 
rafhnose, fructose, arabinose, xylose, dulci- 
tol and glycerol, and no growth in tartaric, 



162 



ORDER I. PSEUDOMONADALES 



citric, acetic or formic acids. No growth 
when asparagine is used as carbon-nitrogen 
source. 

Starch hydrolyzed. 

Temperature relations: Optimum, be- 
tween 25° and 30° C. Slight growth at 11° C. 
No growth at 38° C. 

Chemical tolerance: Optimum pH, be- 
tween 6.8 and 7.3. No growth at pH 8.5; 
slight growth at pH 3.2. 

Aerobic. 

Source: From diseased Desmodium dif- 
fusum in India. 

Habitat: Pathogenic on Desmodium dif- 
fusum, not on D. gangeticum. 

17. Xanthonionas desmodiigangeticii 

Uppal et al., 1948. {Xanthomonas desmodii- 
gangeticii (sic) Uppal, Patel and Moniz, in 
Patel and Moniz, Indian Phytopath., 1, 
1948, 140; also see Patel and Moniz, Curr. 
Sci., 17, 1948, 268.) 

des.mo'di.i.gan.ge'ti.ci.i. M.L. neut.n. 
Desmodium gangeticum name of host species; 
M.L. gen. noun desmodiigangeticii of Des- 
)iiodium gangeticum. 

Rods 0.7 to 1.4 by 1.5 to 2.5 microns. 
Motile with a single flagellum. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Nutrient agar slants: Growth fair, dull, 
flat, opalescent, lemon-chrome. 

Nutrient broth: Moderately turbid. No 
pellicle. 

Milk: Litmus reduced. No tyrosine. 

Nitrites not produced from nitrates. 

Hydrogen sulfide produced. 

Indole not produced. 

Non-lipolytic. 

Uschinsky's solution: Growth. 

Acetylmethjdcarbinol not produced. 

Arabinose, xylose, glucose, galactose, 
fructose, maltose, sucrose, raffinose, manni- 
tol, salicin and sodium citrate are utilized. 
Asparagine utilized as carbon-nitrogen 
source. 

Starch hydrolyzed. 

Salt tolerance: Growth retarded by 3 per 
cent salt; inhibited by 4 per cent salt. 

Temperature relations: Optimum, be- 
tween 20° and 25° C. Minimum, 5°C. Maxi- 
mum, 35° C. 

Aerobic. 



Source: From a disease of Desmodium 
gangeticum found in India. 

Habitat: Pathogenic on Desmodium gange- 
ticum but not on D. diffusum. 

18. Xanthomonas diefFenbachiae (Mc- 
Culloch and Pirone, 1939) Dowson, 1943. 
{Phytomonas dieffenbachiae McCulloch and 
Pirone, Phytopath., 29, 1939, 962; Dowson, 
Trans. Brit. Mycol. Soc, 26, 1943, 12.) 

dief .fen.bach'i.ae. Dieffenbach patro- 
nymic; M.L. fem.n. Dieffenbachia generic 
name; M.L. gen. noun dieffenbachiae oi Dief- 
fenbachia. 

Rods 0.3 to 0.4 by 1.0 to 1.5 microns. 
Encapsulated. Motile with a single polar 
flagellum. Gram-negative. 

Gelatin: Liquefied. 

Beef -infusion peptone agar colonies: 
Slow growing, circular, flat, smooth, trans- 
lucent, butyrous, massicot- to Naples- 
yellow. 

Broth: Turbid. Yellow rim or slight 
pellicle. 

Milk: Slow peptonization and formation 
of tyrosine crystals. Litmus reduced. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

Acid from glucose, sucrose, lactose, 
galactose, fructose and glycerol. Growth 
but no acid in maltose and mannitol. 

Starch moderately hydrolyzed. 

Temperature relations: Optimum, be- 
tween 30° and 31° C. Minimum, 5° C. Maxi- 
mum, between 37° and 38° C. 

Aerobic. 

Source: Seven isolates from diseased 
leaves of Dieffenbachia picta. 

Habitat: Pathogenic on Dieffenbachia 
picta. Artificial infection of Dracaena fra- 
grans. 

19. Xanthomonas hemmiana (Yama- 
moto, 1951) Burkholder, comb. nov. (Phyto- 
monas hemmianus (sic) Yamamoto, Forsch. 
auf dem Gebiet d. Pflanzenkr., 4, 1951, 163.) 

hem.mi.a'na. Named for T. Hemmi, a 
Japanese plant pathologist; M.L. adj. 
hemmianus of Hemmi. 

Rods, 0.3 to 0.7 by 1.3 to 2.2 microns, 
occurring singly or in pairs. Motile with 1 to 
3 polar flagella. Gram-negative. 



FAMILY IV. PSEUDOMONADACEAE 



163 



Gelatin: Liquefied. 

Beef extract agar colonies: Small, circu- 
lar, smooth, flat or raised with regular 
margins, white to pale yellow. 

Beef broth: Moderate clouding. 

Milk: Clearing after coagulation. Litmus 
red. 

Uschinsky's solution: Good growth. 

Cohn's solution: Poor growth. 

Potato: Growthsmooth, copious andolive- 
bufT. 

Nitrites produced from nitrates. 

Indole produced. 

Hydrogen sulfide produced. 

Acid and gas from glucose, sucrose and 
glycerol. Acid from lactose. 

Starch hydrolyzed. 

Temperature relations: Optimum, 32° C. 
Growth above 36° C. and below 2° to 8° C. 

Optimum pH, between 6 and 7; no growth 
below pH 3. 

Aerobic. 

Relationship to other species: This spe- 
cies closely resembles the specie.s placed in 
Aeromonas Kluyver and van Niel. 

Source : Isolated from leaf spot of Jimson 
weed. Datura spp. 

Habitat: Pathogenic on Datura metel, D. 
meteloides, D. inermis, tomato and petunia. 

20. Xaiithomona.s holcicola (Elliott, 
1930) Starr and Burkholder, 1942. {Bac- 
terium holcicola Elliott, Jour. Agr. Res., 40, 
1930, 972; Starr and Burkholder, Phytopath. 
32, 1942, 600.) 

hol.ci'co.la. Gr. holcus kind of grass; 
M.L. mas.n. Holcus generic name of velvet 
grass and sorghum; L. v. cola to dwell ; M.L. 
fem.n. holcicola, Holcus dweller. 

Rods 0.75 by L58 microns. Motile with 
1 or 2 polar flagella. Encapsulated. Gram- 
negative. 

Gelatin: Liquefied. 

Beef -infusion peptone agar colonies: 
Round, umbonate, glistening, smooth, 
translucent to opaque, wax-yellow, buty- 
rous. 

Broth: Trace of growth in 24 hours. Later 
turbid with a slight ring. 

Milk: Casein precipitated and peptonized. 
Alkaline. 

Nitrite production doubtful. 

Indole not produced. 



Hydrogen sulfide produced. 

Lipolytic (Starr and Burkholder, loc. 
cit.). 

Acid but no gas from sucrose. 

Starch hydrolyzed. 

Temperature relations: Optimum, be- 
tween 28° and 30° C. Minimum, 4° C. Maxi- 
mum, between 36° and 37° C. 

pH range for growth: pH 5.5 to 9.0. Opti- 
mum pH, between 7.0 and 7.5. 

Source: Isolated from many collections of 
sorghum leaves showing a streak disease. 

Habitat: Pathogenic on leaves of Holcus 
sorghum and H. halepensis. 

21. Xanthomonas incanae (Kendrick 
and Baker, 1942) Starr and Weiss, 1943. 
(Phytomonas incanae Kendrick and Baker, 
California Bull. 665, 1942, 10; Starr and 
Weiss, Phytopath., 33, 1943, 316.) 

in.ca'nae. L. adj. incanus hoary, gray; 
from host Matthiola incana. 

Rods 0.4 to 0.8 by 0.6 to 2.5 microns. 
Motile with a polar flagellum. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Beef extract agar colonies: Round, 
smooth, convex or pulvinate, glistening, 
margin entire, picric-yellow to amber color. 

Broth: Turbid. 

Milk: No coagulation. A clearing of 
the medium. 

Nitrites not produced from nitrates. 

Indole not produced. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

Acid but no gas from glucose, lactose, 
sucrose, mannitol, d-galactose, xylose, 
d-mannose, raffinose, trehalose and glycerol. 
No acid from maltose, 1-arabinose or 
rhamnose. 

Starch not hydrolyzed. Starch hydrolyzed 
(Burkholder). 

Pectate medium liquefied. 

Tolerates 3 per cent salt. 

Growth in beef broth at pH 4.4. 

Aerobic. 

Distinctive characters: Causes a disease 
of flowering stock but not of cabbage. Dif- 
fers from Xanthomonas campestris in that it 
does not utilize 1-arabinose or maltose. 

Source: Four isolates from diseased plants 
of Matthiola incana. 



164 



ORDER I. PSEUDOMONADALES 



Habitat: Pathogenic on flowering stocks. 

22. Xanthoinouas juglandis (Pierce, 
1901) Dowson, 1939. (Pseudomonas juglandis 
Pierce, Bot. Gaz., 31, 1901, 272; Dowson, 
Zent. f. Bakt., II Abt., 100, 1939, 190.) 

jug.lan'dis. L. juglans, juglandis the wal- 
nut; M.L. fem.n. Juglans generic name of 
walnut; M.L. gen.noun juglandis of the wal- 
nut. 

Description from Miller, Bollen, Sim- 
mons, Gross and Barss (Phytopath., 30, 
1940, 731). 

Rods 0.5 to 0.7 by 1.1 to 3.8 microns. 
Motile with a polar flagellum. Encapsu- 
lated. Gram-negative. 

Gelatin: Liquefied. 

Nutrient glucose-agar streaks: Growth 
abundant, filiform, convex, glistening, 
smooth, opaque, pale lemon-yellow, viscid. 

Broth : Turbid. Ring formed in 2 to 5 days. 

Milk: Enzjmiatic curd that is slowly di- 
gested. Litmus reduced. Crystal formation 
(Burkholder) . 

Nitrites not produced from nitrates. 

Nitrogen sources utilized are peptone, 
aspartic acid, alanine, leucine, sodium 
ammonium phosphate, allantoin, tyrosine, 
uric acid and brucine. 

Indole not produced. 

Hydrogen sulfide not produced on lead 
acetate agar. H2S produced after ZoBell 
and Feltham's method (Burkholder). 

Selenium dioxide reduced. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

Acid but no gas from glucose, fructose, 
galactose, lactose, sucrose, maltose, xylose, 
raffinose, mannitol, glycerol and starch. 
Alkali from salts of citric, lactic, malic and 
succinic acids. Arabinose, rhamnose, dulci- 
tol, salicin, inulin and cellulose not utilized. 

Starch hydrolyzed. 

Pectate medium not liquefied. 

Temperature relations: Optimum, be- 
tween 28° and 32° C. Minimum, between 5° 
and 7° C. Maximum, 37° C. Thermal death 
point, between 53° and 55° C. 

pH range for growth, 5.2 to 10.5. Optimum 
pH, between 6 and 8. 

Source: Isolated from black spots on the 
leaves and nuts of English walnuts, Juglans 
regia. 



Habitat: Pathogenic on the walnut, Jug- 
lans spp. 

23. Xanthomonas lespedezae (Ayers 
et al., 1939) Starr, 1946. (Phytomonas lespe- 
dezae Ayers, Lefebvre and Johnson, U. S. 
Dept. Agr. Tech. Bull. 704, 1939, 19; Starr, 
Jour. Bact., 51, 1946, 136.) 

les.pe.de'zae. Named after Lespedez; 
M.L. fem.n. Lespedeza generic name; M.L. 
gen.noun lespedezae of Lespedeza. 

Rods, 0.56 by 1.62 microns, occurring 
singly, in pairs, or occasionally in short 
chains. Encapsulated. Motile with a single 
polar flagellum. Gram-negative. 

Gelatin: Liquefied. 

Nutrient agar colonies: Circular, raised, 
glistening, translucent, viscid, yellow. 

Broth: Turbid in 48 hours. 

Milk: Peptonized; becomes alkaline. 

Blood serum and egg albumin: Liquefied. 

Nitrites not produced from nitrates. 

Indole produced after 11 days. 

Hydrogen sulfide produced. 

No gas from carbohydrates. 

Starch hydrolyzed. 

Pectate medium liquefied. 

Aerobic. 

Temperature relations: Optimum, near 
35°C. No growth at 5°C. or at 40°C. 

Source: Isolated from diseased Lespedeza 
spp. collected in Virginia, New York and 
Illinois. 

Habitat: Pathogenic on Lespedeza spp. 

24. Xanthomonas maculifoliigarden- 

iae (Ark, 1946) Elrod and Braun, 1947. 
(Phytomonas maculifolium-gardeniae (sic) 
Ark, Phytopath., 36, 1946, 867; Xantho- 
monas maculajoliumgardeniae (sic) Elrod 
and Braun, Jour. Bact., 53, 1947, 515.) 

ma.cu.li.fo'li.i.gar.de'ni.ae. L. fem.n. 
macula a spot; L. neut.n. folium a leaf; M.L. 
neut.n. maculijolium a leaf spot; M.L. 
fem.n. Gardenia the generic name of the 
host; gardeniae of gardenia; M.L. gen.noun 
maculifoliigardeniae of leaf spot of gar- 
denia. 

Rods 0.3 to 0.5 by 1.6 to 2.0 microns. 
Encapsulated. Motile with 1 to 2 polar 
flagella. Gram-negative. 

Gelatin: Slow liquefaction. 

Beef-peptone agar colonies: Growth 



FAMILY IV. PSEUDOMONADACEAE 



165 



rapid. Slightly raised, yellow, butyrous in 
young cultures, difficult to pick up in old 
cultures. 

Broth: Turbid in 24 hours. 

Milk: White curd in bottom. Litmus a 
dirty wine color in supernatant liquid. 

Uschinsky's medium: Good growth. 

Fermi's solution: Scant growth. 

Indole not produced. 

Hydrogen sulfide not produced. 

Nitrites not produced from nitrates. 
Ammonia produced from peptone. 

Acid but no gas from arabinose, glucose, 
fructose, galactose, lactose, maltose, man- 
nitol, raffinose, sucrose and xylose. Glycerol 
not attacked. Tartrate utilized. 

Starch hydrolj^zed. 

Temperature relations: Optimum, be- 
tween 22° and 28° C. Minimum, 10° C. Maxi- 
mum, 37° C. Thermal death point, 50° C. 

Source: Six isolates from gardenia leaf 
spots. 

Habitat : Causes a spot on young leaves of 
gardenias. 

25. Xanthomonas nialvacearum (Erw. 
f Smith, 1901) Dowson, 1939. (Pseudomonas 
nialvacearum Erw. Smith, U. S. Dept. Agr., 
Div. Veg. Phys. and Path., Bull. 28, 1901, 
153; Dowson, Zent. f. Bakt., II Abt., 100, 
1939, 190.) 

mal.va.ce.a'rum. L. malva the mallow; 
M.L. fem.pl.n. Malvaceae the mallow family; 
M.L. fem.pl. gen. n. malvacearum of the mal- 
lows. 

Description from Elliott (Man. Bact. 
Plant Pathogens, 1930, 153) and Lewis 
(Phytopath., 20, 1930, 723). 

Rods. Motile with a single polar fiagellum. 
Gram-negative. 

Gelatin: Liquefied. 

Agar slants: Growth moderate, convex, 
smooth, glistening, pale yellow, wavy to 
irregular margins. 

Broth: Slight to moderate turbidity. 
Sediment. 

Milk: Casein precipitated and slowly di- 
gested. 

Nitrites not produced from nitrates. 

Hydrogen sulfide produced (Burkholder) . 

Not lipolytic (Starr and Burkholder, 
Phytopath., 32, 1942, 600). 

Acid but no gas from glucose, galactose. 



fructose, xylose, lactose, maltose, sucrose, 
raffinose, glycerol, inulin and glycogen. 
Alkaline reaction from salts of acetic, citric, 
lactic and succinic acids. No fermentation 
of arabinose, mannitol, dulcitol, salicin, and 
salts of formic, oxalic and tartaric acids 
(Lewis). 

Starch hydrolyzed (Lewis). 

Pectate medium not liquefied. 

Temperature relations: Optimum, be- 
tween 25° and 30° C. Maximum, between 
36" and 38° C. (Elliott). 

Source: Isolated from angular leaf spot 
of cotton. 

Habitat: Pathogenic on cotton, where- 
ever it is grown, causing a leaf spot, a stem 
lesion and a boll lesion. 

26. Xanthomonas pelargonii (Brown, 
1923) Starr and Burkholder, 1942. (Bac- 
terium pelargoni (sic) Brown, Jour. Agr. 
Res., 23, 1923, 372; Starr and Burkholder, 
Phytopath., 32, 1942, 600.) 

pe.lar.go'ni.i. Gr. pelargus the stork: 
M.L. neut.n. pelargonium generic name of 
stork's bill; M.L. gen. noun pelargonii of 
Pelargonium. 

Rods 0.67 by 1.02 microns. Encapsulated. 
Motile with a single polar fiagellum. Gram- 
negative. 

Gelatin: Slow liquefaction. 

Beef -agar colonies: Cream-colored, glis- 
tening, round, with delicate internal mark- 
ings. 

Broth: Turbid in 24 hours. Incomplete 
pellicle. 

Milk: Alkaline. Clearing in bands. 

Nitrites not produced from nitrates. 

Indole production slight. 

Hydrogen sulfide produced. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

Slight acid but no gas from glucose, su- 
crose and glycerol. 

Starch hydrolysis feebly positive. 

Pectate medium liquefied. 

Temperature relations: Optimum, 27° C. 
Maximum, 35° C. 

No growth in broth plus 3.5 per cent salt. 

Aerobic. 

Source: Isolated from spots on leaves of 
Pelargonium from District of Columbia, 
Maryland and New Jersey. 



166 



ORDER I, PSEUDOMONADALES 



Habitat: Pathogenic on Pelargonium spp. 
and Geranium spp. 

27. Xanthomonas phaseoli (Erw. 

Smith, 1897) Dowson, 1939. {Bacillus 
phaseoli Erw. Smith, Bot. Gaz., U, 1897, 
192; A. A. A. S. Proc, 46 1898, 288; Dow- 
son, Zent. f. Bakt., II Abt., 100, 1939, 190.) 

pha.se'o.li. Gr. phaselus the kidnej^ bean; 
L. phaseolus kidney bean; M.L. mas.n. 
Phaseolus generic name of bean; M.L. gen. 
noun phaseoli of the bean. 

Description from Burkholder (Cornell 
Agr. Exp. Sta. Mem. 127, 1930, 18; Phyto- 
path.,^^, 1932,609). 

Rods 0.87 by 1.9 microns. Motile with a 
single polar flagellum. Gram-negative. 

Gelatin: Liquefied. 

Beef -extract agar colonies: Circular, 
amber-yellow, smooth, butyrous, edges 
entire. 

Broth: Turbid in 24 hours. Yellow ring. 

Milk: Casein precipitated and digested. 
Alkaline. Tyrosine crystals formed. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 3^, 1942,600). 

Acid but no gas from glucose, galactose, 
fructose, arabinose, xjdose, maltose, lactose, 
sucrose, raffinose and glycerol. Alkaline 
reaction from salts of acetic, malic, citric 
and succinic acids. Mannitol, dulcitol, sali- 
cin and formic and tartaric acids not fer- 
mented. 

Starch hydrolj^zed. 

Pectate medium not liquefied. 

Aerobic. 

Very slight growth in beef broth plus 4 
per cent salt (Hedges, Jour. Agr. Res., 29, 
1924, 243). 

Distinctive character: Similar in culture 
to Xanthomonas campestris, X.juglandis, X. 
vesicatoria, etc., but they do not cross 
infect. 

Comments: A variety that produces pus- 
tules on the leaves and pod of soy bean, 
Glycine max, both in America and Japan, 
has been described by Hedges (Science, 66, 
1922, 11). Liquefies pectate medium. 

Two additional varieties have been de- 
scribed which produce a dark brown color 



in a beef extract peptone medium and also in 
tj^rosine medium. The first of these is patho- 
genic on beans (Phaseolus vulgaris) and re- 
lated plants. The second was isolated from 
white kidney beans in India and is patho- 
genic on Phaseolus vulgaris, P. lunatus, P. 
coccineus and Dolichos lablab. 

Habitat: Pathogenic on the bean {Phase- 
olus vulgaris), the hyacinth bean {Dolichos 
lablab) , the lupine {Lupinus polyphyllus) , etc. 
Not pathogenic on the soy bean {Glycine 
sp.) nor cowpea {Vigna sp.). 

28. Xanthomonas plantaginis (Thorn- 
berry and Anderson, 1937) Burkholder, 1948. 
{Phytomonas plantaginis Thornberry and 
Anderson, Phytopath., 27, 1937, 947; Burk- 
holder, in Manual, 6th ed., 1948, 161.) 

plan.ta'gi.nis. L. plantago, plantaginis 
the plantain; M.L. fem.n. Plantago generic 
name of plantain; M.L. gen. noun plantaginis 
of plantain. 

Rods, 0.6 to 1.0 by 1.0 to 1.8 microns, oc- 
curring singly or in chains. Encapsulated. 
Motile with 1 to 2 polar flagella. Gram-nega- 
tive. 

Gelatin: Slight liquefaction. 

Glucose agar slant: Growth moderate, 
filiform, raised, opaque, yellow and viscid. 

Broth: Moderately turbid with ring. 

Milk: Slight acidity, no reduction of lit- 
mus. Peptonization. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced. 

No appreciable amount of gas from carbo- 
hydrates. 

Starch hydrolyzed. 

Temperature relations: Optimum, 25° C. 
Minimum, 12° C. Maximum, 35° C. Thermal 
death point, 50° C. 

Aerobic. 

Source: From diseased leaves of Plantago 
lanceolata in Illinois. 

Habitat: Pathogenic on Plantago spp. 

29. Xanthomonas ricinicola (Elliott, 
1930) Dowson, 1939. {Bacterium ricini Yoshi 
and Takimoto, Jour. Plant Protect., Tokyo, 
16, 1928, 12; Bacterium ricinicola Elliott, 
Man. Bact. Plant Path., 1930, 193; Dowson, 
Zent. f. Bakt., II Abt., 100, 1939, 190.) 

ri.ci.ni'co.la. L. ricinus the castor oil 



FAMILY IV. PSEUDOMONADACEAE 



167 



plant; M.L. mas.n. Kicinus generic name of 
the castor bean; L. v. colo to dwell; M.L. 
fem.n. ricinicola, Ricinus dweller. 

Rods, 0.4 to 0.9 by 1.3 to 2.6 microns, 
occurring in short chains. Encapsulated. 
Motile with polar flagella. Gram-negative. 

Gelatin: Liquefied. 

Nutrient agar colonies: Lemon-yellow, 
changing to brown. 

Milk: Slightly acid. No coagulation. Pep- 
tonization. 

Nitrites not produced from nitrates. 

Acid but no gas from lactose. 

Starch hydrolyzed. 

Temperature relations: Optimum, be- 
tween 29° and 30° C. Minimum, 2.5° C. Maxi- 
mum, 39° C. 

Aerobic. 

Comment: Elliott (loc. cit.) renamed this 
species to avoid confusion with Phytomonas 
ricini Archibald. 

Source: Isolated from leaf -spot of castor 
bean. 

Habitat: Pathogenic on Ricinus com- 



30. Xanthonionas sesbaniae Patel 
et al., 1952. (Patel, Kulkarni and Dhande, 
Curr. Sci.,^^, 1952,74.) 

ses.ba'ni.ae. M.L. fem.n. Sesbania generic 
name of the plant host; M.L. gen. noun 
sesbaniae of Sesbania. 

Rods, 0.7 by 1.3 microns, occurring singly 
or in chains. Encapsulated. Gram-negative. 

Gelatin: Liquefied. 

Potato-glucose agar colonies: Circular, 2 
cm in diameter in 7 daj^s, with striations 
starting 5 mm awaj" from the center up to 
the periphery. Barium-yellow. 

Litmus milk: Slightly peptonized with 
casein digested. Litmus slowly reduced. 

Hydrogen sulfide produced. 

Nitrites not produced from nitrates. 

Acid but no gas from glucose, sucrose and 
lactose. Salicin not attacked. 

Starch hydrolyzed. 

Temperature relations: Optimum, 31° C. 
Thermal death point, 51° C. 

Source: Isolated from leaf spots on jSes- 
bania aegyptiaca. 

Habitat: Pathogenic on Sesbania aegyp- 
tiaca. 



31. Xanthonionas stizolobiicola Patel 
et al., 1951. (Patel, Kulkarni and Dhande, 
Curr. Sci., 20, 1951, 106.) 

sti.zo.Io.bi.i'co.la. M. L. neut.n. Stizolo- 
biutn generic name of host; L. v. colo to 
inhabit; M.L. fem.n. stizolobiicola the 
Stizolobium dweller. 

Rods. Mostly single. Encapsulated. Mo- 
tile. Gram-negative. 

Gelatin: Liquefied. 

Nutrient agar colonies : 8 mm in diameter 
in 4 days, flat, entire, glistening, creamy to 
pinard-yellow. 

Broth: Good growth. 

Synthetic asparagine medium: No growth. 

Loeffller's blood serum: Liquefied in 10 
days. 

Hydrogen sulfide produced. 

Nitrites not produced from nitrates. 

Methyl red negative; acetylmethylcar- 
binol not produced. 

Indole not produced. 

Acid but no gas from glucose, lactose and 
sucrose. Salicin not attacked. 

Starch and casein hydrolyzed. 

Lipolytic. 

Salt tolerance: Up to 3 per cent. 

Optimum temperature, between 28° and 
30° C. 

Aerobic. 

Relationship to other species: Elliott 
(Man. Bact. Plant Path., 2nd ed., 1951, 129) 
lists Xanthomonas phaseoli on Stizolobium 
deeringianum. The two pathogens appear 
similar. 

Source: Isolated from leaves, stems and 
petioles of Stizolobium deeringianum in 
India. 

Habitat: Pathogenic on Stizolobium 
deeringianum. 

32. Xanthonionas taraxaci Nieder- 

hauser, 1943. (Phytopath., 33, 1943, 961.) 

ta.ra.x'a.ci. M.L. neut.n. Taraxacum ge- 
neric name of host; M.L. gen. noun taraxaci 
of Taraxacum. 

Rods, 0.7 to 1.2 by 1.4 to 3.3 microns, 
occurring singly or in pairs. Motile with a 
single polar flagellum. Gram-negative. 

Gelatin: Rapid liquefaction. 

Beef-extract peptone agar colonies: Cir- 
cular, smooth, bright yellow. Growth mod- 
erate. 



168 



ORDER I. PSEUDOMONADALES 



Broth: Turbid with thin ring. 

Milk: Litmus reduced. Soft curd precipi- 
tated and slowly digested. Liquid gradually 
clears. Tyrosine crystals produced. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

Lipase produced. 

Acid from glucose, xylose, galactose, 
fructose, lactose, sucrose and glycerol. 
Arabinose, maltose, raffinose, inulin, manni- 
tol, ethanol and salicin not attacked. Salts 
of acetic, citric, lactic, malic and succinic 
acids utilized with an increase in pH. Salts 
of tartaric, formic, salicylic and benzoic 
acids not utilized. 

Starch hydrolyzed. 

Pectate medium liquefied. 

Salt tolerance: 3.25 to 3.5 per cent. 

Temperature relations: Optimum, 30° C. 
Minimum, between 0° and 3° C. Maximum, 
38° C. 

Aerobic. 

Source: Seven isolates from diseased Rus- 
sian dandelions grown at Ithaca, New York. 

Habitat: Pathogenic on Taraxacum kok- 
Russian dandelion. 



33. Xanthoinonas translucens (Jones 
et al., 1917) Dowson, 1939. (Bacterium trans- 
lucens Jones, Johnson and Reddy, Jour. 
Agr. Res., 11, 1917, 637; Dowson, Zent. f. 
Bakt., II Abt., 100, 1939, 190.) 

trans. lu'cens. L. transluceo to be trans- 
lucent; L. part, translucens being translu- 
cent. 

Rods 0.5 to 0.8 by 1.0 to 2.5 microns. 
Motile with a single polar flagellum. Gram- 
negative. 

Gelatin: Liquefied. 

Beef-peptone agar colonies: Round, 
smooth, shining, amorphous except for 
inconspicuous, somewhat irregular con- 
centric striations within, wax-yellow tinged 
with old gold; margin entire. 

Broth: Turbidity becomes rather strong. 
Pellicle. 

Milk: Soft coagulum and digestion. Milk 
clears. Tyrosine crystals produced. 

Nitrites not produced from nitrates. 

Indole: Slight production. 

Hydrogen sulfide produced. 



Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

Ammonia from peptone. 

Acid but no gas from glucose, d-fructose, 
d-mannose, d-galactose, sucrose, lactose 
and sometimes salicin. No utilization of 
1-rhamnose, inositol, maltose, raffinose, 
inulin, d-mannitol or dulcitol. 

Starch hydrolyzed. 

Pectate medium not liquefied. 

Temperature relations: Optimum, 26° C. 
Minimum, 6° C. Maximum, 36° C. 

Aerobic. 

Distinctive characters: Many forms of 
Xanthomonas translucens have been de- 
scribed, all of which have the same cultural 
characters; they differ mainly in patho- 
genicity. 

Comment: Various varieties, formae spe- 
ciales and races of this species have been 
described. See Elliott (Man. Bact. Plant 
Path., 2nd ed., 1951, 142-146) for details. 

Source : Originally isolated from bacterial 
blight of barley. 

Habitat: Causes water-soaked stripes, 
streaks or other lesions on leaves, culms 
or glumes of grain and related plants. 
Occurs naturally on Triticum spp., Hor- 
deum spp., Bromus spp., Secale cereale, 
Phleum pratense and, by inoculation, on 
Avena spp. 

34. Xanthomonas uppalii Patel, 1948- 
(Indian Phytopath., 1, 1948, 67.) 

up.pa'li.i. Named for B. N. Uppal, an 
Indian plant pathologist; M.L. gen. noun 
uppalii of Uppal. 

Rods, 0.7 to 1.0 by 2.0 to 2.4 microns, 
mostly single. Motile with a single polar 
flagellum. Gram-negative. 

Gelatin: Rapid liquefaction. 

Nutrient agar slants: Growth smooth, 
slightly raised, dull, filiform, opalescent, 
lemon-chrome. 

Potato-glucose agar colonies: Growth 
copious, glistening, butyrous, empire- 
yellow. 

Broth: Turbid. No pellicle. Sediment and 
floccules in 4 days. 

Milk: Growth good. Litmus reduced. 

Indole not produced. 

Hydrogen sulfide produced. 



FAMILY IV. PSEUDOMONADACEAE 



169 



Nitrites and ammonia not produced. 

Acetylmethylcarbinol not produced. 

No growth in Uschinsky's, Cohn's or 
Koser's uric acid medium. 

Acid but no gas from glucose, lactose, 
sucrose, mannitol, raffinose, salicin and 
-xylose. Fructose, arabinose and rhamnose 
not attacked. 

Starch hydrolyzed. 

Temperature relations: Optimum, 30°C. 
Minimum, 10°C. Maximum, 40°C. 

pH range for growth, pH 5.3 to 9.2. Opti- 
mum pH, 7.0. 

Source: Isolated from Iponioea niuricata 
in India. 

Habitat: Pathogenic on Ipomoea nmricata. 

35. Xanthoiiionas vasculoruni (Cobb, 
1893) Dowson, 1939. {Bacillus vascidarum 
(sic) Cobb, Agr. Gaz. of New South Wales, 
Jf, 1893, 777; abst. in Cent. f. Bakt., II Abt., 
1, 1895, 41; Xanthomonas vascularum (sic) 
Dowson, Zent. f. Bakt., II Abt., 100, 1939, 
190.) 

vas.cu.lo'rum. L. vascnlum a small 
vessel; M.L. neut.pl. gen. n. vasculorum of 
small vessels. 

Description from Erw. Smith (Bact. in 
Rel. to Plant Dis., 3, 1914, 54). 

Rods 0.4 by 1.0 micron. Motile with a 
single polar flagellum. Originally reported 
as Gram-variable but later found to be 
Gram-negative (Elliott, Man. Bact. Plant 
Path., 2nded., 1951, 147). 

Gelatin: Liquefaction feeble. Liquefac- 
tion good (Burkholder). 

Beef-e.xtract agar colonies: Pale yellow, 
smooth, glistening, not noticeablj^ viscid. 

Broth: Good growth. 

Milk: Alkaline. 

Nitrites not produced from nitrates. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 3^, 1942, 600). 

Acid but no gas from glucose, fructose 
and glycerol. No acid from lactose. 

Starch hydrolyzed (Burkholder). 

Pectate medium liquefied. 

Temperature relations: Optimum, 28° C. 
Thermal death point, about 50° C. (Elliott, 
op. cit., 1951, 147). 

Source: Isolated from diseased sugar 
cane. 



Habitat: Pathogenic on sugar cane, 
Saccharum officinarum, causing a bacterial 
gummosis. 

36. Xanthomonas vesica torla (Doidge, 
1920) Dowson, 1939. {Bacterium vesicatorium 
Doidge, Jour. Dept. Agr., S. Africa, 1, 1920, 
718; also Ann. Appl. Biol., 7, 1921, 428; 
Dowson, Zent. f. Bakt., II Abt., 100, 1939, 
190.) 

ve.si.ca.to'ri.a. L. vesica a blister; 
M.L. adj. vesicatorius causing a blister. 

Rods 0.6 to 0.7 by 1.0 to 1.5 microns. En- 
capsulated. Motile with a single polar flagel- 
lum. Originally reported as Gram-positive 
but later found to be Gram-negative by 
Gardner and Kendrick (Phytopath., 13, 
1923, 307) and Higgins (Phytopath., 12, 
1922, 513). 

Gelatin: Liquefied. 

Nutrient agar colonies: Good growth. 
Circular, wet-shining, Naples-yellow, edges 
entire. 

Milk: Casein precipitated and slowly 
digested. Tyrosine crystals. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced (Burkholder). 

Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

Acid but no gas from glucose, fructose, 
sucrose, lactose, galactose, glycerol and 
dextrin. 

Certain strains hydrolyze starch, others 
do not (Burkholder and Li, Phytopath., 31, 
1941, 753). 

Pectate medium liquefied. 

Optimum temperature, 30° C. 

Distinctive character: Xanthomonas vesi- 
catoria is reported as pathogenic on toma- 
toes and peppers. However Burkholder and 
Li {loc. cit.) report that there are sufficient 
cultural and pathogenic differences between 
the organism infecting tomatoes and the 
organism infecting peppers to warrant their 
separation into distinct species. 

Comment: A variety pathogenic on 
radishes, turnips and other crucifers, and 
on tomato and peppers, has been described 
by White (Phytopath., 20, 1930, 653). Differs 
from Xanthomonas campestris in that it 
does not cause a vascular disease. Unlike a 



170 



ORDER I. PSEUDOMONADALES 



variety of the latter species, it is not patho- 
genic on horseradish. Originally isolated 
from leaf spots of radishes and turnips in 
Indiana. 

Source: Isolated from spotted tomato 
fruits in South Africa. 

Habitat: Pathogenic on tomatoes, Lyco- 
persicon esculenhim, and peppers, Capsicum 
annuum. 

37. Xanthomonas vignicola Burk- 
holder, 1944. (Phytopath., 34, 1944, 431.) 

vig.ni'co .la. M.L. fem.n. V igna gen&vic 
name of host; L. v. colo to dwell; M.L. 
fem.n. vignicola the Vigna dweller. 

Rods 0.7 (0.46 to 0.92) by 1.76 (1.0 to 
2.8) microns. Motile with a single polar 
flagellum. Gram-negative. 

Gelatin: Liquefied. 

Beef -extract peptone agar slant: Fili- 
form, glistening, edges entire, primuline- 
yellow, butyrous. 

Broth: Turbid in 48 hours; heavy ring; 
no pellicle. 

Litmus milk: Light curd becoming solid. 
Slow peptonization with crystal formation. 
Litmus reduced. Brownish syrup at end of 
6 weeks. 

Hydrogen sulfide produced. 

Indole not produced. 

Nitrites not produced from nitrates. 

Asparagine and tyrosine not utilized as 
carbon-nitrogen sources. Tyrosine broken 
down to a brownish pigment in other media. 

Lipolytic. 

Salt tolerance: 2 per cent retards and 3 
per cent inhibits growth. 

Acid but no gas from glucose, galactose, 
lactose, maltose, sucrose and raffinose. 
Alkaline reactions with salts of citric and 
malic acids. Fructose, 1-arabinose, xylose, 
rhamnose, glycerol, salicin and the sodium 
salts of lactic, formic, succinic, tartaric and 
hippuric acids not attacked. 

Starch hydrolyzed. 

Pectate medium liquefied. 

Aerobic. 

Temperature relations: Optimum, be- 
tween 27° and 30° C. Minimum, between 
6° and 9° C. Maximum, 37° C. 

Source : Six isolates from cankers of cow- 
pea stems. 

Habitat: Causes canker disease of cow- 



peas, Vigna spp., and disease of the red 
kidney bean, Phaseolus vulgaris. 

38. Xanthomonas nakatae (Okabe, 
1933) Dowson, 1943. {Bacterium nakatae 
Type B, Okabe, Jour. Soc. Trop. Agr., 
Formosa, 5, 1933, 161; Dowson, Trans. 
Brit. Mycol. Soc, 26, 1943, 12.) 

na'ka.tae. Named for K. Nakata, a 
Japanese plant pathologist; M.L. gen. noun 
nakatae of Nakata. 

Rods 0.3 to 0.4 by 1.1 to 2.5 microns. 
Encapsulated. Motile with a single polar 
flagellum. Gram-negative. 

Gelatin: Liquefied. Brown color. 

Beef -extract agar colonies: Amber-yellow, 
circular, smooth, glistening, margins entire. 
Medium turns brown. 

Broth: Moderate turbidity with yellow 
ring. Medium turns brown. 

Milk: Casein precipitated and digested. 
Tyrosine crystals produced. Brown color. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced (slight) . 

Acid but no gas from glucose, sucrose, 
maltose and lactose. 

Starch: Active hydrolysis. 

Temperature relations: Optimum, be- 
tween 30° and 32° C. Minimum, 10° C. 
Maximum, 39° C. 

No growth in beef extract broth plus 2 
per cent salt. 

Aerobic. 

Distinctive character: Differs from Type 
A in that it produces a brown pigment in 
culture. (Description of Type A not seen.) 

Source: Isolated from water-soaked to 
brown leaf spots on jute. 

Habitat: Pathogenic on jute, Corchorus 
capsularis. 

39. Xanthomonas papavericola (Bryan 
and McWhorter, 1930) Dowson, 1939. 
(Bacterium papavericola Bryan and Mc- 
Whorter, Jour. Agr. Res., 40, 1930, 9; Dow- 
son, Zent. f. Bakt., II Abt., 100, 1939, 190.) 

pa.pa.ve.ri'co.la. L. papaver the poppy; 
M.L. neut.n. Papaver generic name of 
poppy; L. V. colo to dwell; M.L. fem.n. 
papavericola poppy dweller. 

Rods, 0.6 to 0.7 by 1.0 to 1.7 microns, 
occurring in chains. Encapsulated. Motile 



FAMILY IV. PSEUDOMONADACEAE 



171 



with a single polar flagellum. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Beef agar colonies: Mustard-yellow to 
primuline-yellow, circular, margins entire. 

Broth: Turbidity prompt with a yellow 
ring and an incomplete pellicle. 

Milk: Soft coagulation; peptonization 
and production of tyrosine crystals. 

Nitrates: A weak reaction for nitrites 
after 10 days. 

Indole not produced. 

Hydrogen sulfide produced. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

Acid but no gas from glucose, galactose, 
fructose, sucrose, lactose, maltose, glycerol 
and mannitol. 

Starch hydrolyzed. 

Pectate medium liquefied. 

Temperature relations: Optimum, be- 
tween 25° and 30° C. Maximum, 35° C. 

No growth in broth plus 5 per cent salt. 

Aerobic. 

Source: Isolated from black spots on 
leaves, buds and pods of poppy. 

Habitat: Pathogenic on poppy, Papaver 
rhoeas . 

40. Xaiithomonas alfalfae (Riker 
et al., 1935) Dowson, 1943. (Bacterium al- 
falfae Riker, Jones and Davis, Jour. Agr. 
Res., 51, 1935, 177; Dowson, Trans. Brit. 
Mycol. Soc, £6, 1943, 11.) 

al.fal'fae. Spanish alfalfa (lucerne); 
M.L. gen. noun alfalfae of alfalfa. 

Rods 0.45 by 2.4 microns. Motile with 
a single polar flagellum. Gram-negative. 

Gelatin: Liquefied. 

Nutrient agar slant: Growth abundant, 
filiform, smooth, glistening, butyrous, pale 
yellow. 

Broth: Turbid in 24 hours. Light sedi- 
ment. 

Milk: Casein precipitated and digested. 

Ammonia produced slowly in a nitrate 
medium. 

Acid but no gas from glucose, maltose, 
lactose, arabinose and salicin (Patel, Kul- 
karni and Dhande, Indian Phytopath., 2, 
1949, 166). No acid in yeast broth plus 
sugars. 

Starch hydrolyzed. 



Aerobic. 

Temperature relations: Optimum, be- 
tween 24° and 32° C. Minimum, below 4° C. 
Maximum, below 36° C. 

Source: Six single-cell cultures isolated 
from diseased alfalfa. 

Habitat: Pathogenic on the leaves of 
alfalfa, Medicago saliva. 

41. Xanthomonas acernea (Ogawa, 1937) 
Burkholder, 1948. (Pseudomonas acernea 
Ogawa, Ann. Phyt. Soc. Japan, 7, 1937, 
123; Burkholder, in Manual, 6th ed., 1948, 
165.) 

a.cer'ne.a. L. acerneus made of maple. 

Rods 0.2 to 0.6 by 0.5 to 1.2 microns. 
Motile with a single polar flagellum. Gram- 
negative. 

Gelatin: Liquefied. 

Agar colonies: Round, smooth, convex, 
white to citron-yellow, glistening, trans- 
lucent with amorphous structure. 

Broth: Turbid. 

Milk: Slowly cleared, slightly acid. No 
coagulation. 

Nitrites produced from nitrates. 

Hydrogen sulfide produced. 

No gas produced in peptone water plus 
sugars. 

Starch not hydrolyzed. 

Temperature relations: Optimum, about 
32° C. Thermal death point, 59° C. 

Aerobic. 

Source: From diseased leaves of Acer 
trifidum in Japan. 

Habitat: Causes a disease in Acer spp. 
and in Aesculus turhinata and Koelrenteria 
paniculata. 

42. Xanthomonas carotae (Kendrick, 
1934) Dowson, 1939. (Phytomonas carotae 
Kendrick, Jour. Agr. Res., 49, 1934, 504; 
Dowson, Zent. f. Bakt., II Abt., 100, 1939, 
190.) 

ca.ro 'tae. L. carota the carrot; M.L. 
gen. noun carotae of the carrot. 

Rods 0.42 to 0.85 by 1.38 to 2.75 microns. 
Motile with 1 or 2 polar flagella. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Potato-glucose agar colonies: Circular, 
smooth, glistening, entire, straw-j^ellow in 
color. 



172 



ORDER I. PSEUDOMONADALES 



Milk: Casein precipitated and milk 
cleared; alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

Acid but no gas from glucose, d-galactose, 
xylose, d-mannose, 1-arabinose, sucrose, 
lactose, raffinose, trehalose, d-mannitol 
and glycerol. No acid from maltose or 
rhamnose. 

Starch not hydrolyzed. 

Pectate medium liquefied. 

Optimum temperature, between 25° and 
30° C. 

Tolerates 4 per cent salt at pH 7. 

Aerobic. 

Source: Two original isolations from 
diseased carrots and a reisolation from 
inoculated carrots were used for the descrip- 
tion. 

Habitat : Pathogenic on leaves of Daucvs 
carota var. saliva. 

43. Xanthonionas hederae (Arnaud, 
1920) Dowson, 1939. {Bacterium hederae 
Arnaud, Compt. rend. Acad. Sci., Paris, 
171, 1920, 121; Dowson, Zent. f. Bakt., II 
Abt., 100, 1939, 190.) 

he'de.rae. L. Aedera the ivy; M.L. fem.n. 
Hedera generic name of ivy; M.L. gen. noun. 
hederae of ivy. 

Description taken from Burkholder and 
Guterman (Phytopath., £2, 1932, 783). 

Rods 0.6 by 2.13 microns. Motile with a 
single polar flagellum. Gram-negative. 

Gelatin: Liquefied. 

Beef-extract-agar slants: Growth good, 
filiform, amber-yellow, butyrous. 

Broth: Turbid. 

Milk: Casein precipitated and digested. 
Milk becomes alkaline. 

Nitrites not produced from nitrates. 

Hydrogen sulfide produced. 

Indole not produced. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 32, 1942, 600). 

Acid from glucose, fructose, galactose, 
.xylose, sucrose, lactose and glycerol. Alkali 
from salts of acetic, citric, lactic, malic 
and succinic acids. The following are not 
utilized: arabinose, rhamnose, maltose, 
salicin, cellulose and formic acid. 

Starch not hydrol3^zed. 

Pectate medium not liquefied. 



Aerobic, facultative. 

Source : Isolated from diseased ivy leaves. 
Habitat: Pathogenic on ivy, Hedera 
helix. 

44. Xanthonionas phorniicola (Taki- 
moto, 1933) Dowson, 1943. {Bacterium 
phorniicola Takimoto, Jour. Plant Protect., 
20, 1933, 777; Dowson, Trans. Brit. Mycol. 
Soc, 26, 1943, 12.) 

phor.mi'co.la. Gr. dim. phormi^im the 
name of a plant; M.L. neut.n. Phormium 
generic name of New Zealand flax; L. v. 
colo to dwell; M.L. fem.n. phormicola the 
Phormium dweller. 

Description translated by Dr. K. Togashi. 

Rods 0.5 to 0.6 by 1.0 to 2.0 microns. 
Motile with a single flagellum. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Agar colonies: Light j'ellow, then waxy 
yellow; butyrous, then viscid. 

Broth: Turbid; pellicle formed. 

Milk: Casein coagulated slowly and pre- 
cipitated, then digested. Alkaline. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

No gas from sucrose, glucose, lactose or 
glycerol. 

No acid from various sugars in broth. 

Temperature relations: Optimum, about 
29° C. Minimum, about 0° C. Maximum, 
39° C. 

Aerobic. 

Source: Species isolated from New Zea- 
land flax, Phormixim tenax. 

Habitat: Causes a leaf stripe of Phor- 
mium tenax. 

45. Xanthonionas geranii (Burkholder, 
1937) Dowson, 1939. {Phytomonas geranii 
Burkholder, Phytopath., 27, 1937, 560; 
Dowson, Zent. f. Bakt., II Abt., 100, 1939, 
190.) 

ge . ra'ni . i. Gr. geranium geranium, crane's 
bill; M.L. neut.n. Geranium generic name; 
M.L. gen. noun geranii of Geranium. 

Rods 0.75 to 2.0 microns. Motile with a 
single polar flagellum. Gram-negative. 

Gelatin: Liquefied. 

Beef -extract agar slants: Moderate to 



FAMILY IV. PSEUDOMONADACEAE 



173 



good filiform growth, glistening, primuline- 
yellow. Develops in 24 hours. 

Broth: Turbid in 24 hours. No pellicle 
but a moderate sediment. 

Milk: Becomes clear with a heavy casein 
precipitate. Peptonization with crystal 
formation. 

Nitrates reduced to ammonia. 

Indole not produced. 

Hydrogen sulfide produced. 

Lipolytic (Starr and Burkholder, Phy- 
topath., 32, 1942, 600). 

Acid from glucose, galactose, fructose, 
xylose, rhamnose, lactose, sucrose, raffinose 
and glycerol. Alkaline reaction from salts 
of citric, malic, malonic and succinic acids. 
No growth in arabinose or formic, hippuric, 
maleic or tartaric acids. 

Starch not hydrolyzed. 

Pectate medium liquefied. 

Aerobic. 

Distinctive characters: Pathogenic on 
Geranium spp., not on the house geranium, 
Pelargonium hortorum. 

Relationship to other species: Similar in 
culture to Xanthomonas pelargonii. 

Source: Three cultures isolated from 
Geranium sanguineum. 

Habitat: Pathogenic on Geranium san- 
guineum, G. maculatum, G. praiense and G. 
sylvaticum. 

46. Xanthomonas antirrhini (Taki- 
moto, 1920) Dowson, 1943. (Pseudomonas 
antirrhini Takimoto, Bot. Mag. Tokyo, 34, 
1920, 257; Dowson, Trans. Brit. Mycol. Soc, 
26, 1943, 11.) 

an.tir.rhi'ni. Gr. antirrhinum the plant 
snapdragon; M.L. gen. noun antirrhini of 
the snapdragon. 

Description from Elliott (Man. Bact. 
Plant Path., 1930, 93). 

Rods 0.3 to 0.4 by 0.8 to 1.2 microns. En- 
capsulated. Motile with polar flagella. 
Gram-negative. 

Gelatin: Liquefied. 

Agar colonies: Circular, glistening, white, 
later yellow. 

Milk: Coagulated and casein digested. 

Nitrites produced from nitrates. 

No gas produced. 

Aerobic. 



Temperature relations: Optimum, be- 
tween 26° and 27° C. Maximum, 34° C. 

Habitat: Causes a leaf spot of Aniirr 
hinum niajus. 

47. Xanthomonas heterocea (Vzoroff, 
1930) Sa.vulescu, 1947. {Phytomonas heterocea 
Vzoroff, Bull. North Caucasian Plant 
Prot. Sta. Roztoff-on-Don, 6-7, 1930, 263; 
Sa,vulescu, Anal. Acad. Romane, III, 22, 
1947, 11.) 

he.te.ro'ce.a. Gr. adj. heterus another, 
different. 

Description taken from Rev. App. Myc, 
10, 1931, 628. 

Rods 0.4 to 0.6 by 1.0 to 2.0 microns. 
Motile. Gram-negative. 

Gelatin: Slow liquefaction. 

Agar colonies : Circular, 2 mm in diameter, 
convex, smooth, semi-transparent, glisten- 
ing, yellow to amber. Pitted surface. 

Milk: No coagulation. At first acid, later 
alkaline. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

Acid from glucose, galactose, arabinose, 
xylose, sucrose, maltose, salicin, glycerol 
and mannitol. Does not ferment lactose, 
inulin, ethyl alcohol, esculin, adonitol or 
dulcitol. 

Optimum temperature, between 25° and 
30° C. 

Source: Isolated from diseased tobacco in 
the North Caucasus. 

Habitat: Pathogenic on Nicoliana ta- 
bacum. 

48. Xanthomonas badrii Patel et al., 
1950. (Patel, Kulkarni and Dhande, Indian 
Phytopath.,3, 1950, 104.) 

bad'ri.i. From the given name of Badri 
Uppal, Indian plant pathologist; M.L. 
gen. noun badrii of Badri. 

Rods, 0.7 to 1.0 by 1.4 to 1.8 microns, 
occurring singly and rarely in chains. Motile 
with a single polar flagellum. Gram-nega- 
tive. 

Gelatin: Liquefied. 

Nutrient agar colonies: Smooth, glisten- 
ing, entire, empire-yellow; growth slow. 

Milk: Cleared in 8 days. Litmus reduced. 

Loeffler's blood serum: Liquefied. 



174 



ORDER I. PSEUDOMONADALES 



Nitrites not produced from nitrates. 

Indole not produced. 

Ammonia produced. 

Methjd red negative; acetylmethylcarbi- 
nol not produced. 

Acid but no gas from glucose, lactose, 
sucrose, mannitol and salicin. 

Optimum temperature, 31° C. 

Source: Isolated from leaf spot of Xan- 
thium strumarium in India. 

Habitat: Pathogenic on Xanthium stru- 
marium. 

49. Xanthoinonas guniniisudans (Mc- 
Culloch, 1924) Starr and Burkholder, 1942. 
{Bacterium giunmisudans McCulloch, Phy- 
topath., 14-, 1924, 63; also see Jour. Agr. 
Res., 27, 1924, 229; Starr and Burkholder, 
Phytopath., 32, 1942, 600.) 

gum. mi.su 'dans. L. gummi gum; L. v. 
sudo to sweat, exude; M.L. part. adj. gum- 
misudans exuding gum. 

Rods 0.6 to 0.8 by 1.0 to 2.8 microns. 
Encapsulated. Motile with a single polar 
flagellum. Gram-negative. 

Gelatin: Liquefied. 

Beef-peptone agar colonies: Amber- 
yellow, circular, transparent, smooth, with 
definite margins. 

Broth: Moderately turbid with a yellow 
ring. 

Milk: Soft curd which is digested with 
formation of tyrosine crystals. 

Nitrites not produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

Lipolytic (Starr and Burkholder, loc. cit.). 

Acid from glucose and sucrose. 

Temperature relations: Optimum, 30° C. 
Minimum, 2° C. Maximum, 36° C. 

Aerobic. 

Source: From gummy lesions on gladiolus 
leaves. 

Habitat: Pathogenic on leaves of gladioli. 

50. Xanthonionas nigromaculans (Ta- 
kimoto, 1927) Dowson, 1943. {Bacterium 
nigromaculans Takimoto, Jour. Plant Pro- 
tect., Tokyo, ^, 1927, 522; Dowson, Trans. 
Brit. Mycol. Soc, 26, 1943, 12.) 

ni.gro.ma'cu.lans. L. niger black; L. v. 
maculo to spot; M.L. part. adj. nigromacu- 
lans spotting with black. 



Description translated by Dr. K. Togashi. 

Rods 0.6 to 0.9 by 1.5 to 2.8 microns. 
Motile with 1 or 2 polar fiagella. Gram- 
negative. 

Gelatin: Liquefied. 

Agar colonies: Yellow, circular, entire, 
smooth, glistening. 

Broth: Growth moderate with yellow 
pellicle. 

Milk: Coagulation and digestion of the 
casein. 

Nitrites not produced from nitrates. 

Indole not produced. 

No acid or gas from glucose, sucrose, 
lactose, mannitol or glycerol in peptone 
water. 

Temperature relations: Optimum, be- 
tween 27° and 28° C. Minimum, 0° C. Maxi- 
mum, 33° C. 

Aerobic. 

Comment : A forma specialis that is path- 
ogenic on Zinnia spp. has been described 
(Hopkins and Dowson, Trans. Brit. Mycol. 
Soc, 32, 1949, 253). 

Source: Isolated from lesions on leaf and 
petioles of burdock. 

Habitat: Pathogenic on leaves and peti- 
oles of Arctium lappa, the burdock. 

51. Xanthoinonas axonopodis Starr 
and Garces, 1950. {Xanthomonas axonoperis 
(sic) Starr and Garces, Rev. Fac. Nal. de 
Agron. de Medellin, 12, 1950, 75.) 

ax.on.o'pod.is. Gr. noun axon axis; Gr. 
noun pous foot; M.L. mas.n. Axonopus 
generic name of a grass; M.L. gen. noun 
axonopodis of Axonopus. 

Rods 0.4 by 1.0 to 3.0 microns. Encapsu- 
lated. Motile by means of a single polar 
flagellum. Gram-negative. 

Gelatin: Not liquefied. 

Yeast extract agar: Growth slow; small, 
yellow colonies appear in 7 days. 

Peptone sucrose agar: Growth slow; yel- 
low colonies 1 mm in diameter appear in 7 
days. 

Potato-glucose agar: No growth. 

Broth: Slight turbidity in two days; 
slimy pellicle in 2 weeks. Yellowish ring 
produced. 

Milk: Litmus not reduced. 

Nitrites not produced from nitrates. 

Indole not produced. 



FAMILY IV. PSEUDOMONADACEAE 



175 



Hydrogen sulfide not produced. 

Non-Iipolytic. 

Tyrosine in a caseinate medium: Growtli 
slight; no color reaction. 

Carbohj'drate utilization difficult to 
determine because of meager growth. Glu- 
cose, sucrose and trehalose probably uti- 
lized. Lactose, maltose, raffinose, dulcitol, 
gl,ycerol, mannitol, sorbitol, dextrin, inulin, 
aesculin and salicin utilization doubtful. 

Starch hydrolyzed. 

Pectate medium not liquefied. 

Temperature relations: Optimum, 30° C. 
Minimum, 5° C. Maximum, 37° C. 

Moderate growth in broth plus 1 per cent 
NaCl; no growth with 1.5 per cent NaCl. 

Chemical tolerance: Optimum pH be- 
tween 6.6 and 7.6. Minimum, 5.8. 

Source: Isolated from diseased grass, 
Axonopus scoparius, in Colombia. 

Habitat: Pathogenic on Axonopvs spp. 

52. Xanthonionas oryzae (Uyeda and 
Ishiyama, 1926) Dowson, 1943. (Pseudo- 
monas oryzae Uyeda and Ishiyama, Proc. 
Third Pan-Pacific Sci. Congr., Tokyo, 2, 
1926, 2112; Dowson, Trans. Brit. Mycol. 
Soc, 26, 1943, 12.) 

o.ry'zae. Gr. oryza rice; M.L. fem.n. 
Oryza generic name of rice; M.L. gen. noun 
oryzae of Oryza. 

Rods 0.5 to 0.8 by 1.0 to 2.0 microns. 
Motile with a single polar flagellum. Gram- 
negative. 

Gelatin: No liquefaction. 

Nutrient agar colonies: Circular, smooth, 
glistening, wax-j-ellow. 

Milk: Slightly acid. 

Nitrites not produced from nitrates. 

Hydrogen sulfide produced. 

Acid but no gas from glucose, lactose and 
sucrose. 

Optimum temperature, between 26° and 
30° C. 

Strict aerobe. 

Source: Isolated from a leaf blight of rice. 

Habitat: Pathogenic on rice, Oryza saliva. 

53. Xanthonionas celebensis (Giiu- 
mann, 1923) Dowson, 1943. {Fseiidomonas 
celebensis Gaumann, Ztschr. f. Pflanzen- 
krank., SS, 1923, 11; Meded. Inst, voor 
Plantenziek., Buitenzorg, 59, 1923, 17; 



Dowson, Trans. Brit. Mycol. Soc, 26, 1943, 
11.) 

ce.le.ben'sis. Celebes, an island name; 
M.L. adj. celebensis of Celebes. 

Rods 0.9 by 1.5 microns. Motile by a 
single polar flagellum. Gram-negative. 

Agar colonies: Graj'ish yellow. 

Broth: Thin pellicle. 

Milk: Coagulated and cleared. 

Nitrites not produced from nitrates. 

Sodium selenite: Brick red. 

Starch hydrolyzed. 

Source: From vascular bundles of dis- 
eased bananas from the Celebes. 

Habitat: Causes the blood disease of 
banana. 

54. Xanthonionas panici (Elliott, 1923) 
Savulescu, 1947. (Bacterium panici Elliott, 
Jour. Agr. Res., 26, 1923, 157; Sivulescu, 
Anal. Acad. Romane, III, 22, 1947, 11.) 

pa'ni.ci. L. panicum Italian panic grass; 
M.L. neut.n. Panicum generic name; M.L. 
gen. noun panici of Panicum. 

Rods 0.69 by 1.66 microns. Encapsu- 
lated. Motile with 1, rarely 2, polar flagella. 
Gram-negative. 

Gelatin: Liquefaction slow. 

Beef agar colonies: Circular, white, 
smooth, glistening, margins at first entire, 
later undulate. 

Broth: Moderate turbidity in 24 hours. 
Thin pellicle. Medium brownish. 

Milk: Alkaline and clears. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

No acid or gas from carbohydrates. 

Starch: Hydrolysis moderate. 

Temperature relations: Optimum, 33° C. 
Minimum, 5° C. Maximum, 45° C. 

pH range for growth, pH 5.4 to 10.0. 
Optimum pH, between 6.15 and 6.3. 

Aerobic. 

Distinctive characters: Differs from 
Pseudomonas andropogoni in that it liquefies 
gelatin, produces nitrites from nitrates and 
does not infect sorghum and broom corn. 

Source: Isolation from water-soaked le- 
sions on leaves, sheaths and culms of millet 
collected in Wisconsin and in S. Dakota. 

Habitat: Pathogenic on i)roso millet, 
Panicum miliaceum. 



176 



ORDER I. PSEUDOMONADALES 



55. Xanthomonas proteamaculans 

(Paine and Stansfield, 1919) Burkholder, 
1948. (Pseudomonas proteamaculans Paine 
and Stansfield, Ann. Appl. Biol., 6, 1919, 
38; Burkholder, in Manual, 6th ed., 1948, 
169.) 

pro.te.a.ma'cu.lans. Gr. Proteus a god; 
M.L. noun Protea a plant generic name; L. 
V. maculo to spot; M.L. part. adj. 'proteama- 
culans spotting Protea. 

Rods 0.6 to 0.8 by 0.8 to 1.6 microns. 
Motile with 1 to 3 polar flagella. Gram- 
positive (Paine and Stansfield). Gram-nega- 
tive (Dowson, personal communication, 
August, 1953). 

Gelatin: Liquefied. 

Agar slant: Growth wet-shining, dirty 
white with a faint yellow tinge. 

Broth: Turbid in 24 hours. Slight ring. 

Milk: Acid with soft curd after 2 days. 
Later a separation of whey. 

Nitrites produced from nitrates. 

Acid and gas from glucose, sucrose and 
mannitol. No acid or gas from lactose. 

Starch: Slight hydrolysis. 

Source: Repeated isolation from a leaf- 
spot of Protea in England. 

Habitat: Pathogenic on Protea cynar- 
oides . 

56. Xanthomonas manihotis (Ar- 
thaud-Berthet, 1912) Starr, 1946. {Bacillus 
manihotus (sic) Arthaud-Berthet, in Bon- 
dar, Chacaras and Quintaes, 5 (4), 1912, 
15; Starr, Jour. Bact., 51, 1946, 136.) 

ma.ni.ho'tis. M.L. Manihot a plant 
generic name; M.L. gen. noun manihotis of 
Manihot. 

Description from Burkholder (Phyto- 
path.,S^, 1942, 147). 

Rods 0.35 to 0.93 by 1.4 to 2.8 microns. 
Mostly non-motile. One isolate showed a 
few cells with a single polar flagellum. 
Amaral (Instit. Biol., Sao Paulo, Arq., 
IS, 1942, 120) states that the species is mo- 
tile with a single polar flagellum. Gram- 
negative. 

Gelatin: Liquefied. 

Beef -extract-peptone agar slant: Growth 
raised, ivory-colored, smooth, shiny, with 
edges entire. 

Potato-glucose agar: Growth abundant, 
white to hyaline, very mucoid. 



Broth: Turbid with a whitish granular 
ring. 

Litmus milk: Litmus reduced and milk 
clears. With return of color, litmus is purple. 

Indole not produced. 

Hydrogen sulfide produced. 

Nitrites produced from nitrates (Drum- 
mond and Hipolito, Ceres, 2, 1941, 298). 

Asparagine not used as a nitrogen and 
carbon source. No growth in nitrate syn- 
thetic broth. 

Weak growth but slight acid production 
in synthetic medium plus glucose, d-galac- 
tose, d-fructose, d-xylose, maltose or su- 
crose. No growth in rhamnose, 1-arabinose, 
d-lactose, glycerol, mannitol or salicin. 
Good growth with alkaline reaction in same 
medium plus salts of the following acids: 
acetic, citric, malic, maleic or succinic. 
The salts of formic, hippuric, lactic and 
tartaric acids were not utilized. 

Starch hydrolyzed. 

Pectate medium liquefied. 

Lipolytic action slight. 

Aerobic. 

Temperature relations: Optimum, 30° C. 
Minimum, 5° C. Maximum, 38° C. 

Source: First isolated from the cassava. 
Manihotus utilissima, in Brazil. 

Habitat: Produces a wilt disease on 
various species of Manihotus. 

57. Xanthomonas rubrisubalbioans 

(Christopher and Edgerton, 1930) Savu- 
lescu, 1947. {Phytomonas rubrisubalbicans 
Christopher and Edgerton, Jour. Agr. Res., 
41, 1930, 266; Sivulescu, Anal. Acad. Ro- 
mane. III, 22, 1947, 11.) 

ru.bri. sub. al'bi. cans. L. ruber red; L. 
subalbicans whitish; M.L. adj. rubrisubalbi- 
cans red whitish. 

Short rods with polar flagella. En- 
capsulated. Gram-negative. 

Gelatin: No liquefaction. 

Bacto-glucose agar colonies: Circular, 
glistening, viscid, milky gray to buff. 
Margins translucent, entire. 

Broth: Turbid after 24 hours. Pellicle 
and a ropy sediment. 

Indole produced. 

Hydrogen sulfide produced. 

No acid or gas from carbohydrates. 

Starch hydrolyzed. 



FAMILY IV. PSEUDOMONADACEAE 



177 



Optimum temperature, 30° C. 

Optimum pH, 6.8 to 8.0. 

Source: Isolated many times from mot- 
tled stripe of sugar cane in Louisiana. 

Habitat: Pathogenic on sugar cane. 
Johnson's grass and sorghum 

58. Xanthomonas cannae (Bryan, 1921) 
Savulescu, 1947. (Bacterium cannae Bryan, 
Jour. Agr. Res., 21, 1921, 152; Sivulescu, 
Anal. Acad. Romane, III, 22, 1947, 12.) 

can'nae. Gr. carina a reed; M.L. fem.n. 
Canna generic name; M.L. gen. noun cannae 
of Canna. 

Rods 0.5 to 0.7 by 1.0 to 2.0 microns. 
Encapsulated. Motile with 1 to 3 polar 
flagella. Gram-negative. 

Gelatin: Slow liquefaction. 

Agar slants: Growth filiform, white, 
moist, with thin margins and granular 
centers. 

Broth: Turbid; heavy sediment. 

Milk: Alkaline and clears. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

No acid produced from carbohydrates. 

Temperature relations: Optimum, 35° C. 
Minimum, 5° C. Maximum, 40° C. 

Aerobic. 

Source: Isolated from diseased canna 
leaves collected in Washington, D. C. and 
in Illinois. 

Habitat: Causes a disease in Canna 
indica. 

59. Xanthomonas conjac (Uyeda, 
1910) Burkholder, 1948. {Pseudomonas 
conjac Uyeda, Bot. Mag. Tokyo, 24, 1910, 
182; Burkholder, in Manual, 6th ed., 1948, 
171.) 

con'jac. M.L. conjac the specific epithet 
of Amorphophallus konjac, the host. 

Description from Elliott (Man. Bact. 
Plant Path., 19,30, 121). 

Rods 0.75 to 1.0 by 1.5 microns. Motile 
with 1 to 4 polar flagella. Presumably Gram- 
negative although the original description 
records this species as Gram-positive (Burk- 
holder). 

Gelatin colonies: Circular to irregular, 
light yellow. 

Broth : Pellicle formed. 



Milk: Coagulated. 
Conjac: Liquefied. 
Nitrites produced from nitrates. 
Indole produced. 
Hydrogen sulfide produced. 
Gas from glucose. 
Optimum temperature, 24° C. 
Habitat: Pathogenic on Amorphophallus 
konjac. 

60. Xanthomonas zingiber! (Uyeda, 
1908) SSvulescu, 1947. (Eine neue species, 
Uyeda, Cent. f. Bakt., II Abt., 17, 1907, 
383; Pseudomonas zingiheri Uyeda, Rept. 
Imp. Agr. Exp. Sta., Japan, No. 35, 1908, 
114; Savulescu, Anal. Acad. Romane, III, 
22, 1947, 13.) 

zin.gi'be.ri. Gr. indecl. zingiheri ginger. 

Description from Stapp (in Sorauer, 
Handb. d. Pflanzenkrank., 2, 5 Aufl., 1928, 
65). 

Rods 0.5 to 1.1 by 0.75 to 1.8 microns. 
Non-motile at first, later a polar flagellum 
develops. Gram-negative. 

Gelatin: Liquefied. 

Agar colonies: White. 

Milk: Coagulation and peptonization of 
the casein. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide produced. 

No gas from glucose. 

Temperature relations: Optimum, 28° C. 
Minimum, 5° C. Maximum, 40° C. 

Source: Isolated from ginger plant show- 
ing a rot at the base of the sprouts. 

Habitat: Pathogenic on ginger. Zingiber 
officinale. 

Addendum: Species inceriae sedis. Two 
additional groups of yellow, polar-flagellate 
species are described in this addendum al- 
though they are not typical of the genus 
Xanthomonas in all respects. The first is a 
group of three species of plant pathogens. 
One of these species is non-motile, but it ap- 
pears to be closely related to the two polar- 
flagellate species with which it is associated. 
Plant pathologists have placed these three 
species in Xanthomonas even though they do 
not possess all of the characteristics of the 
species in this genus senszi stricto. The 
non-water-soluble, yellow pigment differs 



17i 



ORDER I. PSEUDOMONADALES 



from that found in true xanthomonads. 
Likewise none of the three species liquefies 
gelatin. Neither do they show the gummy 
growth of true xanthomonads, and they 
differ in other important characteristics. 
The second group comprises eleven species 
which are not pathogenic to plants so far 



as is known. They have been isolated from 
the surface of leaves, soil and similar ma- 
terials. All produce a non-water-soluble, 
yellow pigment, but no one has as yet under- 
taken a comparative study of cultures to 
determine which of these species, if any, 
are true xanthomonads. 



Key to Xanthomonas Addendum. 

I. Plant pathogens. 

A. Non-motile. 

1. Xanthomonas stewartii. 

B. Polar flagellate. 

1. Litmus milk alkaline. Pathogenic on 7ns spp. 

2. Xanthomonas tardicrescens. 

2. No change in litmus milk. Pathogenic on sugar cane, Saccharum officinarum. 

3. Xanthomonas albilineans. 
II. Saprophytic species. 

A. Gelatin liquefied. 

1. Nitrites produced from nitrates. 

a. Acid but no gas from glucose. 

4. Pseudomonas trifolii. 

5. Pseudomonas xanthe. 
aa. Action on glucose not recorded. 

6. Pseudomonas caudata. 

2. Nitrites not produced from nitrates. 

a. Litmus milk acid; ferments lactose. 

7. Pseudomonas perlurida. 
aa. Litmus milk slimy, alkaline. 

8. Pseudomonas ochracea. 

B. Gelatin not liquefied. 

1. Nitrites produced from nitrates. 

a. Do not attack cellulose. 

b. Does not attack phenol. 

9. Pseudomonas cerevisiae. 
bb. Attacks phenol. 

10. Pseudomonas pictorum. 
aa. Attack cellulose. 

b. Litmus milk acid but no digestion. 

11. Pseudomonas arguta. 
bb. No growth in litmus milk. 

12. Pseudomonas subcreta. 

2. Nitrites not produced from nitrates; may or may not hydrolyze agar. 

a. Butter-colored pellicle on litmus milk. 

13. Pseudomonas lacunogenes. 
aa. No surface pellicle. 

14. Pseudomonas segnis. 



Group I. -Plant pathogens. 
1. Xanthomonas stewartii (Erw. 
Smith, 1914) Dowson, 1939. (Sweet corn 
bacillus, Stewart, N. Y. Agr. Exp. Sta. Bull. 



130, 1897 , 423; Bacterium stewarti (sic) Smith, 
Bacteria in Relation to Plant Diseases, S, 
1914, 89; Xanthomonas stewarti (sic) Dow- 
son, Zent. f. Bakt., II Abt., 100, 1939, 190.) 



FAMILY IV. PSEUDOMONADACEAE 



179 



ste.war'ti.i. Stewart patronymic; JVI.L. 
gen. noun stewartii of Stewart. 

Description from Smith (U. S. Dept. 
Agr., Div. Veg. Phys. and Path., Bull. 28, 
1901). 

Rods 0.4 to 0.7 by 0.9 to 2.0 microns. 
Encapsulated. Non- motile (McCulloch, 
Phytopath., 8, 1918, 440). Gram-negative. 

Gelatin: No liquefaction. 

Nutrient agar colonies: Small, round, 
yellow. 

Broth: Growth feeble with whitish ring 
and yellow precipitate. 

Milk: Yellow ring but no visible action 
on the milk. Slightly acid. 

Nitrites not produced from nitrates. 
McNew (Phytopath., 28, 1938, 773) states 
that less virulent strains assimilate only 
organic nitrogen; those of intermediate 
virulence assimilate nitrogen from inorganic 
salts without reduction of nitrates to ni- 
trites; virulent strains reduce nitrates to 
nitrites. 

Hydrogen sulfide not produced. 

Indole production slight or none. 

Reduction of methylene blue in Dun- 
ham's solution feeble or doubtful. 

Acid but no gas from glucose, galactose, 
sucrose, mannitol and glycerol. No acid 
from maltose. Acid from fructose, arabinose 
and xylose (McNew, loc. cit.); also from 
lactose and mannose (Dowson, op. cit., 
100, 1939, 190). 

Starch not hydrolyzed. 

Temperature relations: Optimum, 30° C. 
Maximum, 39° C. Minimum, 8° C. 

Chemical tolerance: Optimum pH be- 
tween 6.0 and 8.0. Limits, about pH 4.5 to 
8.5. 

8 per cent salt restricts growth. 

Strict aerobe. 

Source: From wilted sweet corn. 

Habitat: Pathogenic on corn, Zea mays. 
Sweet corn very susceptible and field corn 
slightly so. 

2. Xanthomouas tardicrescens (Mc- 
Culloch, 1937) Dowson, 1943. (Bacterium 
tardicrescens McCulloch, Phytopath., £7, 
1937, 135; Dowson, Trans. Brit. Mycol. Soc, 
26, 1943, 12.) 

tar.di.cres'cens. L. adj. tardus slow; L. 



part. adj. crescens growing; M.L. adj. tardi- 
crescens slow growing. 

Rods 0.6 to 0.8 by 1.58 microns. Motile 
with a polar flagellum. Gram-negative. 

Gelatin: No liquefaction. 

Beef -extract agar colonies: Circular, 
mustard -yellow, edges entire, 1.0 to 1.5 mm 
in diameter. 

Broth: Light clouding. 

Milk: Slightly alkaline. Clearing after 5 
to 6 weeks. 

Nitrites produced from nitrates. 

Indole not produced. 

Hydrogen sulfide not produced, or feebly 
so. 

Acid but no gas from glucose, fructose, 
galactose, arabinose, xylose and rhamnose. 
Alkaline reaction from salts of citric, malic 
and succinic acids. 

Starch not hydrolyzed. 

Not lipolytic (Starr and Burkholder, 
Phytopath., 82, 1942, 603). 

Temperature relations: Optimum, 26° C. 
Maximum, 32° C. Minimum, 5° C. (McCul- 
loch, Phytopath., 28, 1938, 648). 

Chemical tolerance: Optimum pH be- 
tween 6.5 and 7.5. Growth slight at 5.8 and 
8.0 (McCulloch, loc. cit.). 

No growth with 3 per cent salt (McCul- 
loch, loc. cit.). 

Aerobic. 

Distinctive character: Very slow grower. 

Source: Isolated by McCulloch and by 
Burkholder from blighted iris leaves. 

Habitat: Pathogenic on Iris spp. 

3. Xanthomonas albilineans (Ashby, 
1929) Dowson, 1943. {Bacterium albilineans 
Ashby, Trop. Agr., Trinidad, 6, 1929, 135; 
Dowson, Trans. Brit. Mycol. Soc, .^5,1943, 
11.) 

al.bi.li'ne.ans. L. adj. albus white; L. 
part. adj. lineans striping; M.L. adj. albili- 
neans white-striping. 

Description from Martin, Carpenter and 
Weller (The Hawaiian Planters' Record, 
36, 1932, 184). 

Rods, 0.25 to 0.3 by 0.6 to 1.0 micron, 
occurring singly or in chains. Motile with a 
polar flagellum. Gram-negative. 

Agar colonies: After 7 to 10 days, minute 
transparent drops, moist, shining. Honey- 
yellow to Naples -yellow. 



180 



ORDER I. PSEUDOMONADALES 



Gelatin: No liquefaction. 

Milk: Growth, but no visible change in 
the milk. 

No growth with ammonium salts, nitrates 
or asparagine as a source of nitrogen. 

No growth in peptone water without 
carbohydrates. Invertase secreted. 

Starch not hj'drolyzed. 

Temperature relations: Optimum, about 
25° C. Maximum, 37° C. 

Distinctive characters: Differs from 
Xanthomonas vasculorum, which produces a 
large gummy type of colony and which is 
a very active organism biochemically. The 
two pathogens also differ in the type of 
lesion they produce on sugar cane. 

Source : Isolated by D. S. North (Colonial 
Sugar Ref. Co., Sydney, N. S. Wales, Agr. 
Rept., 8, 1926, 1) from white stripe and leaf 
scald of sugar cane in Australia. 

Habitat: Vascular pathogen of sugar 
cane, Saccharum officinarum. 

Group II. — Saprophytic species. 

4. Pseudomonas trifolii Huss, 1907. 
(Huss, Cent. f. Bakt., II Abt., 19, 1907, 68; 
Xanthomonas trifolii James, Canadian Jour. 
Microbiol., 1, 1955, 479.) 

tri.fo'li.i. L. trifoUum trefoil, clover; 
M.L. neut.n. TrifoUum generic name of 
clover; M.L. gen. noun trifolii of TrifoUum. 

Rods, 0.5 to 0.7 by 0.75 to 2.0 microns, 
occurring singly, in pairs and in chains. 
Motile, possessing a single polar flagellum. 
Gram-negative. 

Gelatin colonies: Convex, smooth, moist, 
glistening, grayish yellow. 

Gelatin stab: Napiform liquefaction. 

Agar colonies: Small, circular, grayish, 
becoming brownish yellow. 

Agar slant: Yellowish, becoming brown- 
ish yellow streak, lacerate margin. 

Broth: Turbid, with grayish yellow pel- 
licle and sediment. 

Litmus milk: Slowly coagulated; alkaline; 
with yellow ring. 

Potato: Thick, yellowish, fiat, smooth, 
glistening. 

Hydrogen sulfide produced. 

Indole produced. 

Acid from glucose, sucrose, xylose, arabi- 
nose and mannitol. No acid from lactose. 

Nitrites produced from nitrates. 



Cultures have an agreeable odor. 

Volutin formed. 

Aerobic, facultative. 

Optimum temperature, between 33° and 
35° C. 

Source: Isolated from clover hay. 

Habitat: Evidently a common organism 
on the leaves of plants. 

5. Pseudomonas xanthe Zettnow, 1916. 
Cent. f. Bakt., I Abt., Orig., 77, 1916, 220.) 

xan'tha. Gr. adj. xanthus yellow. 

Rods 0.5 to 0.6 by 0.4 to 1.4 microns. 
Motile, possessing a single or occasionally 
two or more very long (20 microns) polar 
flagella. Gram-negative. 

Gelatin colonies: Circular, yellow, granu- 
lar. 

Gelatin stab: Pale yellow surface growth. 
Brownish j^ellow under surface colonies. 
Saccate liquefaction. 

Agar slant: Dark yellow, glistening, with 
dark yellow sediment in water of condensa- 
tion. Pigment not water-soluble. 

Broth: Turbid. 

Milk becomes rose-yellow in 4 weeks with- 
out anj^ other change. 

Potato: Grayish yellow to brownish 
growth. 

Indole produced. 

Nitrites produced from nitrates. 
Acid produced from glucose, sucrose and 
maltose. 

Starch hydrolyzed. 

Blood serum not liquefied. 

Aerobic, facultative. 

Optimum temperature, 30° C. 

Source: Air contamination. 

6. Pseudomonas caudata (Wright, 
1895) Conn, 1919. (Bacillus caudatus Wright, 
Memoirs Nat. Acad. Sci., 7, 1895, 444; 
Conn, Jour. Agr. Res., 16, 1919, 313.) 

cau.da'ta. L. noun canda a tail; M.L. adj. 
caudatus having a tail. 

Rods long, granular, slender, occurring 
singly, in pairs and in chains. Appear like 
cocci in old cultures. Motile, possessing a 
polar flagellum (Conn). Gram-negative. 

Gelatin colonies: Yellow, translucent, 
smooth, undulate. 

Gelatin stab: Villous growth in stab. 
Crateriform liquefaction. 



FAMILY IV. PSEUDOMONADACEAE 



181 



Agar slant: Yellow to orange, glistening, 
translucent, slightly spreading. May lose 
power to form pigment. 

Broth: Turbid, with yellow sediment. 

Litmus milk: Unchanged. 

Potato: Dark yellow, raised, rough, 
spreading. 

Indole not produced. 

Nitrites and ammonia produced from 
nitrates. 

Ammonia produced from peptone. 

Starch digested. 

Aerobic, facultative. 

Optimum temperature, 25° C. 

Habitat: Water and soil. 

7. Pseudonionas perlurida Kellerman 
et al., 1913. (Kellerman, McBeth, Scales 
and Smith, Cent, f . Bakt., II Abt., S9, 1913, 
516; also see McBeth, Soil Sci., /, 1916, 
472.) 

per.lu'ri.da. L. prefi.x per very; L. luridus 
pale yellow, sallow; M.L. adj. perluridus 
verj' sallow. 

Rods 0.4 by 1.0 micron. Motile with one 
to three polar flagella. Gram-negative. 

Gelatin stab: Liquefied. 

Agar slant: Moderate, flat, faint yellow 
growth. 

Broth: Turbid in 5 days. 

Litmus milk: Acid. Peptonization after 
16 days. 

Potato: Scant, 3'ellow growth with 
bleaching along line of growth. 

Indole not produced. 

Nitrites not produced from nitrates. 

Ammonia produced. 

Acid from glucose, maltose, lactose, 
sucrose, starch, glycerol and mannitol. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Source: Soil from Virginia, Louisiana 
and Missouri. 

Habitat: Soil. 

8. Pseudonionas ochracea (Zimmer- 
mann, 1890) Chester, 1901. {Bacillus ochra- 
ceus Zimmermann, Bakt. unserer Trink- 
und Nutzwasser, Chemnitz, /, 1890, 60; 
Chester, Man. Determ. Bact., 1901, 316.) 

och.ra'ce.a. Gr. noun ochra ochre; M.L. 
adj. ochraceus of the color of ochre. 

Rods, 0.7 to 0.8 by 1.2 to 4.5 microns, 
occurring in pairs and longer chains. Slow, 



undulatory motion (Zimmermann). Polar 
flagella (Lehmann and Neumann, Bakt. 
Diag., 1 Aufl., 2, 1896, 255). Gram-negative. 

Gelatin colonies: Pale yellow to golden, 
ochre-yellow, slightly raised, with slightly 
fringed margin, granular. 

Gelatin stab: Yellowish to yellow -gray 
surface growth. Infundibuliform lique- 
faction. Pale yellow to ochre-yellow sedi- 
ment. 

Agar colonies: Thin, flat, yellowish, 
smooth. 

Agar slant: Thin, yellowish gray to 
ochraceous growth. 

Broth: Slightly turbid, with pale yellow 
sediment. 

Litmus milk: Medium becomes slimv: 
alkaline. 

Potato: Ochre-yellow streak. 

Indole produced. 

Nitrites not produced from nitrates. 

Hydrogen sulfide produced. 

Aerobic, facultative. 

Optimum temperature, 35° C. 

Source: Chemnitz tap water. 

Habitat: Water. 

9. Pseudonionas cerevisiae Fuhrmann, 
1906. (Cent. f. Bakt., II Abt., 16, 1906, 309.) 

ce.re.vi'si.ae. L. cerevisia beer; M.L. 
gen. noun cerevisiae of beer. 

Rods straight or slightly curved, 0.6 
by 1.5 to 2.0 microns, occurring singly and 
in chains. Motile, possessing a tuft of four 
to six polar flagella. Gram-negative. 

Gelatin colonies: Circular, white, slightly 
contoured, becoming brownish yellow. 

Gelatin stab: Slight yellowish growth in 
stab. No liquefaction. 

Agar colonies: Thin, spreading, con- 
toured. 

Agar slant: Moist, glistening, thin, pale 
yellow, spreading, contoured. 

Litmus milk: Slow coagulation. 

Potato: Yellowish brown, spreading 
growth. 

Indole not produced. 

Nitrites produced from nitrates. 

No gas from glucose. 

Aerobic, facultative. 

Optimum temperature, 30° C. 

Source: Isolated from beer. 

Habitat: Unknown. 



182 



ORDER I. PSEUDOMONADALES 



10. Pseudomonas pictorum Gray and 
Thornton, 1928. (Cent. f. Bakt., II Abt., 73, 
1928, 89.) 

pic.to'rum. Named for the Picts, a Scot- 
tish tribe; M.L. neut.pl. gen. n. 'pictorum of 
the Picts. 

Rods 0.5 to 0.8 by 1.5 to 5.0 microns. 
Motile, usually with a single polar flagel- 
lum. Gram-negative. 

Gelatin colonies: Circular, greenish 
yellow, convex, smooth, glistening, entire. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular, yellow, conve.x, 
smooth, glistening, entire. 

Agar slant: Filiform, yellow, convex, 
smooth, glistening, entire. 

Broth: Turbid. 

Nitrites produced from nitrates. 

Starch not hydrolyzed. 

Acid from glucose and maltose. 

Attacks phenol. 

Aerobic, facultative. 

Optimum temperature, 25°C. 

Source: One culture from soil. 

Habitat: Soil. 

11. Pseudomonas argiita McBeth, 1916. 
(Soil Science, 1, 1916, 465.) 

ar.gu'ta. L. part. adj. argutus clear, 
bright. 

Rods 0.3 by 0.8 micron. Motile with one 
or two polar flagella. Gram-negative. 

Gelatin stab : Moderate, yellowish growth. 
No liquefaction in 30 daj^s. 

Agar colonies: Circular, slightly convex, 
soft, grayish white, granular, entire. 

Agar slant: Scant, grayish white growth. 

Potato agar slant: Moderate, yellowish, 
glistening growth. 

Broth: Turbid. 

Ammonia cellulose agar: Enzymatic zone 
2 to 3 mm in 30 days. 

Filter paper broth: Paper is reduced to 
loose flocculent mass which disintegrates 
very readily on slight agitation. More rapid 
decomposition when the broth contains 
ammonium sulfate, potassium nitrate, pep- 
tone or casein as source of nitrogen. 

Litmus milk: Acid, not digested. 

Potato: No growth. 

Indole not produced. 

Nitrites produced from nitrates. 

Ammonia not produced. 



Acid from glucose, maltose, lactose and 
starch. No acid from glycerol, mannitol or 
sucrose. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Source: Isolated twice from California 
soils. 

Habitat: Soil. 

12. Pseudomonas subcreta McBeth and 
Scales, 1913. (Bur. Plant Industry, U. S. 
Dept. Agr., Bull. 266, 1913, 37.) 

sub.cre'ta. L. pref. sub- somewhat; L. 
creta chalk; M.L. adj. subcretus somewhat 
chalky. 

Rods 0.3 by 1.4 microns. Motile with one 
to five polar flagella. Gram-negative. 

Gelatin stab: Filiform growth, no lique- 
faction. 

Cellulose agar: No surface growth. 
Moderate, generally faint yellow growth 
in medium, area of growth sunken. 

Agar slant: Glistening, smooth, moist, 
vitreous to faint yellow growth. 

Starch agar: Enzymatic zone 2 to 4 mm. 

Broth: No growth. 

Litmus milk: No growth. 

Potato: Growth scant, concave due to 
slight liquefaction, white to faint yellow. 
Bleached around growth. 

Indole not produced. 

Trace of nitrites produced from nitrates. 

Ammonia not produced. 

Acid from glucose, lactose, maltose, 
sucrose and starch. No acid from glycerol 
or mannitol. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Habitat: Soil. 

13. Pseudomonas lacunogenes Gores- 
line, 1933. (Jour. Bact., £6, 1933, 447.) 

la.cu.no'ge.nes. L. lacuna a hollow; L. 
gicjno to produce; M.L. adj. lacunogenes pro- 
ducing hollows. 

Short rods, 0.2 to 0.3 by 1.0 to 1.2 microns, 
with pointed ends, occurring singly or in 
pairs. Motile with a single polar flagellum 
from 2 to 15 microns in length. Gram-nega- 
tive. 

Plain gelatin stab: No growth. 

Nutrient gelatin stab: Growth brownish 
yellow, half-way down stab, heavier at 
surface. No liquefaction. 



FAMILY IV. PSEUDOMONADACEAE 



183 



Nutrient agar colonies: Small, yellow; 
surface of the agar pitted or dimpled. After 
5 days colonies 5 to 7 mm in diameter, 
orange-yellow, slightly raised, surrounded 
b.y a depression. 

Nutrient agar slant: Growth heavy, light 
orange-yellow; consistency of warm butter; 
edge entire, slightly raised. Shallow de- 
pression formed on each side of streak. 
Agar softened beneath growth. 

Nutrient broth: Turbid in 48 hours. Light 
orange-j'ellow pellicle; considerable, viscous 
sediment. 

Litmus milk: Alkaline; butter-colored 
pellicle. Reduction in bottom of tube after 
10 daj's. No curd. No digestion. 

Potato: Growth moderate, orange-yellow, 
smooth. No darkening. 

Indole not produced. 

Nitrites not produced from nitrates. 

Starch agar plates not hydrolyzed. 

Utilizes arabinose, galactose, lactose, 
fructose, maltose, melezitose, raffinose, 
starch, xj-lose, glucose, mannose, sucrose, 
pectin, rhamnose, salicin and dextrin. No 
growth in dulcitol, erythritol, glycerol, 
sorbitol, mannitol or inulin. 

Temperature relations: Optimum, 28° C. 
Good growth at 25° C. Moderate growth at 
20° and at 37° C. No growth at 10° and at 
42° C. 

Limits of pH: 5.4 to 10.0. 

Aerobic, facultative. 

Distinctive characters: Softens agar; 
considerable change in viscosity of agar due 
to this digestion; utilization of ammonium 
sulfate as nitrogen source. 

Source: Three cultures isolated from an 
experimental trickling filter receiving 
creamery wastes. 

Habitat: Probably widely distributed in 
nature. 

14. Pseudonionas segnis Goresline, 
1933. (Jour. Bact., 26, 1933, 452.) 
seg'nis. L. adj. segnis slow, tardy. 



Short rods, 0.2 to 0.3 by 1.0 to 1.2 microns, 
with pointed ends, occurring singly or in 
pairs. Motile with a single polar flagellum. 
Gram-negative. 

Plain gelatin stab: No growth. 

Nutrient gelatin stab: Growth yellow, 
half-way down stab, best at surface. No 
liquefaction. 

Nutrient agar colonies: Very small, light 
yellow surface pitted. After 5 days colonies 
5 mm in diameter. 

Nutrient agar slant: Growth heavy, 
orange -yellow, consistency of warm butter; 
edge entire, slightly raised; slight de- 
pression formed on each side of growth. 
Agar softened beneath growth. 

Nutrient broth: Turbid in 48 hours. No 
pellicle or surface growth. Moderate amount 
of sediment. Old cultures with a yellow ring 
at surface and occasionally a loose mem- 
brane. 

Litmus milk: Slightly alkaline after 10 
daj's. No reduction. No surface growth. 

Potato: Scant j'ellow-orange growth. No 
darkening. 

hidole not produced. 

Nitrites not produced from nitrates. 

Hydrogen sulfide not produced. 

Starch not hydrolyzed. 

Arabinose, glucose, galactose, lactose, 
fructose, maltose, mannose, xylose, sucrose, 
melezitose and raffinose utilized. 

Temperature relations: Optimum, 28° C. 
Good growth at 25° C. Moderate growth at 
20° and at 37° C. No growth at 10° and at 
42° C. 

Limits of pH: 5.8 to 9.0. 

Aerobic, facultative. 

Distinctive characters: Softens agar; con- 
siderable change in viscosity of agar due to 
this digestion. 

Source: Isolated from an experimental 
trickling filter receiving creamery wastes. 

Habitat: Probably widely distributed in 
nature. 



Genus III. Acetobacter Beijerinck, 1898.* 

{Acetobacter Beijerinck, quoted from Krai's Sammlung v. Mikroorg., Prague, 1898, 7; 
Acetobacterium in Ludwig's abstract of Hoyer, Bijdrage tot de kennis van de azijnbacterien, 

* Revised by Dr. Reese H. Vaughn, Univ. of California, Berkeley, California, June, 
1943, and Davis, California, March, 1954. 



184 ORDER I. PSEUDOMONADALES 

Thesis, Leiden, 1898, 115 pp.. Delft, in Cent. f. Bakt., II Abt., 4, 1898, 857; Acetobader 
Beijerinck, Proc. Kon. Akad. v. Wetenschapp., Amsterdam, 2, 1900, 503; Acetobacter Bei- 
jerinck. Arch, n^erl. d. sciences exact, et natur., S^r. II, 6, 1901, 212; Acetobacter in Fuhr- 
mann, Beiheft Bot. Centralbl., Orig., 19, 1905, 8; Acetimonas Orla-Jensen, Cent. f. Bakt., 
II Abt., 22, 1909, 312; Acetobacter Winslow et al.. Jour. Bact., 5, 1920, 201; Acetomonas 
Leifson, Antonie van Leeuwenhoek, 20, 1954, 109.) 

A.ce.to.bac'ter. L. noun acetum vinegar; M.L. mas.n. bacter the masculine form of the 
Gr. neut.n. bactrum a rod or staff; M.L. mas.n. Acetobacter vinegar (acetic) rod. 

Individual cells ellipsoidal to rod-shaped, occurring singly, in pairs or in short or long 
chains. Motile with polar flagella*, or non-motile. Involution forms may be spherical, 
elongated, filamentous, club-shaped, swollen, curved or may even appear to be branched. 
Young cells Gram-negative; old cells often Gram- variable. Obligate aerobes; as a rule 
strongly catalase-positive, sometimes weakly so. Oxidize various organic compounds to 
organic acids and other oxidation products which may undergo further oxidation. Com- 
mon oxidation products include acetic acid from ethyl alcohol, gluconic and 5-keto- 
gluconic acid from glucose, dihydroxy-acetone from glycerol, sorbose from sorbitol, etc. 
Nutritional requirements vary from simple to complex. Development generally best in 
yeast infusion or yeast autolysate media with added ethyl alcohol or other o.xidizable sub- 
strates. Optimum temperature varies with the species. Widely distributed in nature where 
they are particularly abundant in plant materials undergoing alcoholic fermentation; 
of importance to man for their role in the completion of the carbon cycle and for the pro- 
duction of vinegar. 

It is recognized that there are marked morphological and physiological similarities be- 
tween species of Acetobacter and Pseudomonas (see Vaughn, Jour. Bact., 46, 1943, 394; and 
Stanier, Jour. Bact., 54, 1947, 191, among others). However, the species of Acetobacter may 
be differentiated from all other Pseudomonadaceae by their unique ability to oxidize sig- 
nificant quantities of ethanol under the extremely acidic conditions imposed by the 
presence of from about 2 to more than 11 per cent acetic acid. 

The evidence also indicates a significant difference in the end-products of hexose and di- 
saccharide oxidation. The species of Acetobacter produce gluconic and 5-ketogluconic acids 
from both glucose and maltose whereas species of Pseudomonas oxidize glucose to gluconic 
and 2-ketogluconic acids and maltose to maltobionic acid (see Pervozvanski, Khim. Referat. 
Zhur., 7, 1939, 43; Lockwood, Tabenkin and Ward, Jour. Bact., 4^, 1941, 51; Stodola and 
Lockwood, Jour. Biol. Chem., 171, 1947, 213; Kluyver, Deley and Rijven, Antonie van 
Leeuwenhoek, 16, 1950, 1; and Foda and Vaughn, Jour. Bact., 65, 1953, 233, among others). 

The type species is Acetobacter aceti (Beijerinck) Beijerinck. 

Key to the species of genus Acetobacter. 

I. Oxidize acetic acid to carbon dioxide and water. 

A. Utilizes ammonium salts as a sole source of nitrogen (Hoyer's solution). f 

1. Acetobacter aceti. 

* Leifson (Bact. Proc, 53rd Gen. Meeting Soc. Amer. Bact., 1953, 34, and Antonie van 
Leeuwenhoek, 20, 1954, 102), in a study of the flagellation of cultures of Acetobacter, reports 
that the species of Acetobacter that oxidize acetic acid are peritrichous, and that the species 
that do not oxidize acetic acid ordinarily have four polar flagella. Further photographs such 
as can be obtained with the electron microscope must, however, be obtained before the exact 
point of attachment of the flagella can be determined with certaint3^ 

t It is not known with certainty whether Acetobacter pasteurianus and Acetobacter kuetz- 
ingianus are capable of using inorganic nitrogen as a sole source of nitrogen for growth. 
See Acetobacter rancens Beijerinck to which these two species are very closely related. Also 
see Frateur, La Cellule, 53, 1950, 316^320. 

Species Nos. 2 to 3b inclusive will, however, utilize ammonium salts if supplied with 



FAMILY IV. PSEUDOMONADACEAE 



185 



B. Do not utilize ammonium salts as a sole source of nitrogen. 

1. Forms a thick, zoogloeal, cellulose membrane on the surface of liquid media. 

2. Acetobacter xylinum. 

2. Do not form a thick, zoogloeal, cellulose membrane on the surface of liquid media. 

3. Acetobacter rancens. 

3a. Acetobacter pasteurianus . 
3b. Acetobacter kuetzingianus . 
II. Do not oxidize acetic acid. 

A. Form pigments in glucose media. 

1. Dark brown to blackish pigment. 

4. Acetobacter melanogenus. 

2. Pink to rose pigment. 

5. Acetobacter roseus. 

B. Do not form pigments. 

1. Optimum temperature, between 30° and 35° C. 

6. Acetobacter suboxydans. 

2. Optimum temperature, between 18° and 21° C. 

7. Acetobacter oxydans. 



1. Acetobacter aceti (Beijerinck, 1898) 
Beijerinck, 1900. (Mycodermes, Pasteur 
Compt. rend. Acad. Sci., Paris, 54, 1862 
265; Pasteur, ibid., 55, 1862, 28; Mycoderma 
aceti Pasteur, Ann. Sci. d. Ecole Normal 
superiore, 1, 1864, 103-158; Bacterium aceti 
Beijerinck, Cent. f. Bakt., II Abt., 4, 15 
211; Acetobacter aceti Beijerinck, published 
as a synonym in Krai's Sammlung v. Mikro 
org., Prague, 1898, 7; Beijerinck, Proc. Kon 
Akad. V. Wetensch., Amsterdam, 2, 1900 
503.) 

a.ce'ti. L. noun acetum vinegar; L. gen 
noun aceti of vinegar. 

Beijerinck's description of this organism 
which forms the basis of the description 
given here, is based on Pasteur's earlier de 
scription.* 

Rods, 0.4 to 0.8 by 1.0 to 2.0 microns, oc 
curring singly and in long chains, frequently 
showing large club-shaped forms. Stain yel 
low with iodine solution. Motility variable 
Motile cells possess a single polar flagellum 
(Vaughn, Jour. Bact., 46, 1943, 394). 

Beer gelatin containing 10 per cent su- 
crose: Large, shiny colonies are formed. 



Liquid media: Forms slimy pellicle; may 
also form a ring or turbidity without pel- 
licle. 

Acid from glucose, ethanol, propanol and 
glycol. No acid from arabinose, fructose, 
galactose, sorbose, sucrose, maltose, lactose, 
raffinose, dextrin, starch, glycogen, inulin, 
methanol, isopropanol, butanol, isobutanol, 
pentanol, glj'cerol, erythritol, mannitol, 
dulcitol or acetaldehyde (Henneberg, Die 
deutsch. Essigind., 2, 1898, 147). 

Distinctive characters : Marked oxidative 
power causing rapid and complete oxidation 
of substrate such as glucose or ethyl alcohol ; 
ability to utilize inorganic nitrogen salts as 
a sole source of nitrogen (Hoyer, Inaug. 
Diss., Leiden, 1898, 43; Beijerinck, Cent. f. 
Bakt., II Abt., 4, 1898, 215); growth and 
oxidative activity in association with fer- 
menting yeasts (Vaughn, Jour. Bact., 36, 
1938, 360). 

Optimum temperature, 30° C. Growth 
occurs between 10° and 42° C. 

Habitat: Vinegar, souring fruits, vege- 
tables and beverages. 



other required nutrients (Stokes and Karsen, Jour. Bact., 49, 1945, 495; Foda and Vaughn, 
Jour. Bact., 65, 1953,79). 

* Beijerinck (op. cit., 4, 1898, 211) explains the relationship of Pasteur's organism to 
those described by others as follows: "Two of the many varieties of B. (Bacterium) rancens 
have been described by Henneberg under the names B. oxydans and B. acetosum. Hansen 
erroneously named this species B. aceti as did Brown also. Neither Hansen nor Brown 
knew B. aceti of Pasteur." 



186 



ORDER I. PSEUDOMONADALES 



2. Acetobacter xylinum (Brown, 
Holland, 1920. {Bacterium xylinum Brown, 
Jour. Chem. Soc, London, Jfi, 1886, 439; 
Holland, Jour. Bact., 5, 1920, 216.) 

xy'li.num. Gr. adj. xylinus of cotton; L. 
neut.n. xylinum cotton. 

Rods, about 2 microns long, occurring 
singl}^ and in chains. The cells have a slimy 
envelope which gives the cellulose reaction. 

A zoogloeal film forms on all liquid media 
in which growth occurs; the nature of the 
medium influences the thickness of the film 
which may vary from 2 to 250 millimeters. 
The film becomes cartilagenous and falls 
to the bottom if disturbed. 

X-ray pattern studies made by Khouvine, 
Champetier and Sutra (Compt. rend. Acad. 
Sci. Paris, IH, 1932, 208) and by Barsha and 
Hibbert (Can. Jour. Research, 10, 1934, 
170) have shown that the cellulose contained 
in the membranes formed by Acetobacter 
xylinum is identical with cotton cellulose. 

Acid from glucose, ethanol, propanol and 
glycol. No acid from arabinose, fructose, 
galactose, maltose, lactose, raffinose, dex- 
trin, starch, methanol, isopropanol, bu- 
tanol, isobutanol, pentanol, mannitol or 
acetaldehyde (Henneberg, Die deutsch. 
Essigind., 2, 1898, 147). 

Distinctive character: The production of 
thick, leather}'', zoogloeal, cellulosic mem- 
branes on the surface of liquids. 

Optimum temperature, 28° C. 

Habitat: Vinegar, souring fruits, vege- 
tables and beverages. 

3. Acetobacter rancens Beijerinck, 1898. 
{Bacterium rancens Beijerinck, Cent. f. 
Bakt., II Abt., 4, 1898, 211; Beijerinck, in 
Krai's Sammlung v. Mikroorg., Prague, 
1898, 4.) 

ran'cens. L. part. adj. rancens putrid, 
stinking. 

The following description is taken in part 
from a study of a culture of Acetobacter 
rancens received from Kluyver by Vaughn; 
also see Frateur (La Cellule, 53, 1950, 339). 

Rods with the usual morphological ap- 
pearance of cultures of acetic-acid bacteria. 
Gram-negative. Molitility variable. Motile 
cells possess a single polar fiagellum 
(Vaughn, Jour. Bact., ^6, 1943, 394). Involu- 



tion forms commonly appear as filaments 
and enlarged cells. 

Wort agar slant: Growth abundant, 
butyrous, pale-buff in color in one week. 

Yeast infusion, glucose, calcium carbon- 
ate slant: Growth abundant, butyrous and 
cream-colored in one week. 

With petri-dish cultures, well isolated 
colonies are large, smooth and butyrous on 
the above-mentioned media. 

Broth cultures containing peptone or 
yeast infusion form a mucilaginous, slimy 
pellicle. Beijerinck {op. cit., 4, 1898, 211) 
called this polysaccharide pellicle cellulose- 
like and intimated that the mucilaginous 
material in the pellicle was somewhat 
different from that produced by Acetobacter 
xylinutn. The pellicle material stained blue 
when treated with iodine and hydroiodic 
acid. 

Minimum nutritional requirements: Pan- 
tothenic acid, nicotinic acid, p-aminoben- 
zoic acid, thiamine, valine, alanine, isoleu- 
cine, histidine, cystine, proline, aspartic or 
glutamic acid, mineral salts and an oxidiz- 
able substrate such as alcohol, glucose, etc. 
(Foda and Vaughn, Jour. Bact., 65, 1953, 
79). 

Acid from glucose, ethanol, propanol, 
butanol, glycol, adonitol, mannitol and sor- 
bitol. No acid from numerous other com- 
pounds tested. 

Distinctive character: Production of a 
thin, mucilaginous, slimj^, polysaccharide 
membrane on the surface of liquids as com- 
pared with the thick, true cellulose mem- 
brane of Acetobacter xylinum grown under 
the same conditions. Beijerinck {op. cit., 4-, 
1898, 211) reported the production of a 
cellulose-like membrane with some cultures 
of Acetobacter rancens. 

Source: Isolated from shavings in the 
quick- vinegar process. 

Habitat: Found in fermented grain mash, 
malt beverages, mother of vinegar, and 
souring fruits. 

Beijerinck (Cent. f. Bakt., II Abt., 4, 
1898, 211) thought that the next two species 
were hardly more than varieties of Acetobac- 
ter rancens; also see Frateur (La Cellule, 
53, 1950, 339). 



FAMILY IV. PSEUDOMONADACEAE 



187 



3a. Acetobacter pasteurianus (Han- 
sen, 1879) Beijerinck, 1916. (Mycoderma 
pasteurianum Hansen, Compt. rend. d. 
Trav. d. Lab. d. Carlsberg, 1, 1879, 96; Bei- 
jerinck, Proc. Sect. Sci., Kon. Akad. v. 
Wetenschappen, Amsterdam, 18, 1916, 1199.) 

pas.teur.i.a'nus. Named for Pasteur, 
French chemist and bacteriologist; M.L. 
adj . pasteurianus of Pasteur. 

Rods, 0.4 to 0.8 by 1.0 micron, occurring 
singly and in chains, at times showing thick, 
club-shaped forms. Motility variable. 
Motile cells possess a single polar flagellum 
(Vaughn, Jour. Bact., 46, 1943, 394). Stain 
blue with iodine. 

Wort gelatin colonies: Small, circular, 
entire, gray, slimy. 

Forms a dry, wrinkled, folded pellicle on 
double beer with one per cent alcohol. 

Meat infusion gelatin: Growth wide- 
spread; later rosette form, toothed. 

Acid from glucose, ethanol, propanol and 
glycol. No acid from arabinose, fructose, 
galactose, sorbose, sucrose, maltose, lactose, 
raffinose, dextrin, starch, glycogen, inulin, 
methanol, isopropanol, butanol, isobutanol, 
pentanol, glycerol, erythritol, mannitol, 
dulcitol or acetaldehyde (Henneberg, Die 
deutsch. Essigind., 2, 1898, 147). 

Optimum temperature, 30° C. Growth 
occurs between 5° and 42° C. 

Habitat: Vinegar; beer and beer wort. 

3b. Acetobacter kuetzingianus (Han- 
sen, 1894) Bergey et al., 1923. {Bacterium 
klitzingianum (sic) Hansen, Compt. rend. d. 
Trav. d. Lab. d. Carlsberg, 3, 1894, 191; 
Bergey et al.. Manual, 1st ed., 1923, 35.) 

kuet.zing.i.a'nus. Named for Kuetzing, 
a German botanist; AL L. adj. kuetzingianus 
of Kuetzing. 

Short, thick rods, occurring singly, rarely 
forming chains of notable length. Capsule 
stains blue with iodine and with potassium 
iodide. Non-motile. 

Double beer gelatin colonies: Small, en- 
tire, w'ith vermiform surface. 

Wort gelatin colonies: Small, entire, with 
surface free of wrinkles. 

Double beer: Forms a rather thick, folded 
pellicle. Distinguished from Acetobacter 



aceti in showing a heavier growth above the 
surface of the medium. 

Acid from glucose, ethanol, propanol and 
glycol. No acid from arabinose, fructose, 
galactose, sorbose, sucrose, maltose, lactose, 
rafiinose, dextrin, starch, glycogen, inulin, 
methanol, isopropanol, butanol, isobutanol, 
pentanol, glycerol, erythritol, mannitol, 
dulcitol or acetaldehyde (Henneberg, Die 
deutsch. Essigind., 2, 1898, 147). 

Optimum temperature, 34° C; minimum, 
between 6° and 7° C; maximum, 42° C. 

Habitat: Beer. Found in double beer. 

4. Acetobacter inelanogenus Beije- 
rinck, 1911. (Cent. f. Bakt., II Abt., 29, 
1911, 175.) 

me.la.no'ge.nus. Gr. adj. melas, melanis 
black; Gr. v. gennao to produce; M.L. adj. 
inelanogenus black-producing. 

Rods. Non-motile or motile. Motile cells 
possess a single polar flagellum (Vaughn, 
Jour. Bact., 46, 1943, 394). 

Gelatin: Apparent liquefaction probably 
caused by acid, not an enzyme. When held 
on artificial media for some time, the power 
of liquefying gelatin is lost, probably due to 
a slower production of acid. Deep brown pig- 
ment produced; gelatin becomes insoluble 
in boiling water and in trypsin solution. 

Beer- or wort-gelatin plates: Characteris- 
tic dark brown, wide-spreading, diffuse 
areas. 

Tap water - agar - glucose - peptone - potas- 
sium phosphate-iron citrate-chalk medium: 
In 24 hours at 30° C, black, spreading, dif- 
fuse areas. 

Produces the pigment from peptone or 
yeast autolysate if maltose or glucose is 
present as a source of carbon. When grown in 
glucose-peptone broth or agar with CaCOa 
at 25° to 30° C, the pigment is produced 
after one to several weeks. 

Pigment : The pigment causing the brown 
coloration is an aromatic substance which is 
blackened by iron salts. Reduces alkaline 
solutions of silver and mercury, blackening 
them (Beijerinck, op. cit., 29, 1911, 175). 

Minimum nutritional requirements : Pan- 
tothenic acid, nicotinic acid, p-aminoben- 
zoic acid, thiamine, mineral salts and an 
oxidizable substrate such as alcohol, glu- 



188 



ORDER I. PSEUDOMONADALES 



cose, etc. (Gray and Tatum, Proc. Nat'l. 
Acad. Sci., 30, 1944, 404, and Foda and 
Vaughn, Jour. Bact., 65, 1953, 79). 

Acetic acid produced from alcohol. Glu- 
conic and 5-ketogluconic acids produced 
from glucose and maltose. 

O.xidizes mannitol to fructose; sorbitol to 
sorbose; and glj^cerol to dihydroxj^acetone. 
Produces acid from arabinose, .xylose, glu- 
cose, fructose, galactose and maltose. Some 
strains do not attack maltose. 

Distinctive character: The formation of 
dark brown to black pigment in media con- 
taining glucose. 

Source: Isolated from beer. 

Habitat : Causes light-colored beer to be- 
come darker brown. It is a very strong beer- 
vinegar bacterium. Also found in souring 
fruits. 

5. Acetobacter roseus Vaughn, 1942. 
{Bacterium hoshigaki var. rosea Takahashi 
and Asai, Zent. f. Bakt., II Abt., 82, 1930, 
390; Vaughn, Wallerstein Lab. Communica- 
tions, 5, No. 14, 1941,20.) 

ro'se.us. L. adj roseus rose -colored. 

Rods, 0.7 to 0.9 by 1.5 to 1.8 microns, 
generally occurring singly, in pairs, often 
in chains. Non-motile. Pellicle on fluid 
media yields no starch or cellulose reaction. 

Koji (a mixture of rice and mold spores 
used to start fermentation of Japanese bread 
and sake) extract agar colonies: Small, 
granular, circular, glistening, umbonate, 
becoming brownish. 

Wort agar colonies: Circular, milky 
white, becoming brownish in the center and 
yellowish at the periphery. 

Koji extract agar streak: Grayish white, 
glistening with ciliate margin, becoming 
purple-brown to brown. 

Koji extract: Turbid, with thin film as- 
cending on wall of tube. 

Bouillon: Turbid with ring formation. 

Yeast infusion glucose agar: Colonies 
similar to those on wort agar. 

Yeast infusion glucose broth: Turbid with 
thin, ascending film. 

Red color produced on sake-wort agar and 
all media containing calcium carbonate. 

Acid from glucose, fructose, galactose, 
arabinose, glycerol, mannitol, ethanol and 
propanol. No acid from maltose, sucrose. 



lactose, raffinose, de.xtrin, starch, inulin, 
sorbitol, glycogen, isodulcitol or methanol. 

Optimum temperature, between 30° and 
35° C; minimum, between 10° and 15° C; 
maximum, between 40° and 41° C. 

Thermal death point, 50° C. for 5 minutes. 

Distinctive character: The formation of a 
rose to red pigment in suitable media, par- 
ticularly those containing glucose and cal- 
cium carbonate. 

Note: Vaughn {loc. cit.) has proposed the 
name Acetobacter roseus to replace the name 
Acetobacter hoshigaki. As originally de- 
scribed, this organism was given the name 
Bacterium hoshigaki var. rosea by Takahashi 
and Asai {op. cit., 82, 1930, 390) without the 
authors having first named and described 
the species Bacterium hoshigaki. The Japa- 
nese word "hoshigaki" has been used in a 
confusing manner, viz. Bacterium indiis- 
trium var. hoshigaki (Takahashi and Asai, 
loc. cit.) and Bacterium hoshigaki var. 
glucuronicum I, II and III (Takahashi and 
Asai, Jour. Agr. Chem. Soc. Japan, 9, 1933, 
351 and Zent. f. Bakt., II Abt., 87, 1933, 
385). None of these Japanese names are in 
the form of true binomials. 

Source: Isolated from fermenting mash of 
dried persimmons (hoshigaki) ; also from 
souring figs and dates. 

6. Acetobacter suboxydans Kluyver 
and de Leeuw, 1923. (Paper read at the con- 
vention of the Dutch Society of Micro- 
biology, Utrecht, December, 1923; see 
Tijdschrift v. Vergelijkende Geneeskunde, 
10, Afl. 2-3, 1924.) 

sub. ox'y. dans. L. pref. sub- somewhat, 
slightly; Gr. adj. oxys sharp; M.L. part. adj. 
oxydans oxidizing; M.L. part. adj. suboxydans 
slightly o.xidizing. 

Short rods. Occur singly or in chains. 
Non-motile. Morphologically like Aceto- 
bacter rancens. 

Forms a very thin, hardlj' visible pellicle 
on fluid media. 

Wort agar colonies: Very small, circular, 
slightly yellow. 

Minimum nutritional requirements: Pan- 
tothenic acid, nicotinic acid, p-aminoben- 
zoic acid, valine, alanine, isoleucine, 
histidine, cystine, proline, mineral salts 
and an oxidizable substrate such as alcohol, 



FAMILY IV. PSEUDOMONADACEAE 



189 



glucose, etc. (Landy and Dicken, Jour. 
Biol. Chem., H6, 1942, 109; Lampen, Under- 
kofler and Peterson, Jour. Biol. Chem., 1^6, 
1942, 277; Underkofler, Bantz and Peterson, 
Jour. Bact., 45, 1943, 183; Stokes and Lar- 
sen, Jour. Bact., J^, 1945, 495). 

Acid from ethanol, propanol, glycol, 
glucose, glycerol and sorbitol. 

Optimum temperature, 30° C. 

Distinctive character: Partial o.xidation 
of substrates as indicated by the formation 
of calcium 5-ketogluconate crystals on the 
surface of agar slants containing glucose and 
calcium carbonate. 

Source: Isolated from spoiled beer. 

Habitat: Beer; also found in souring 
fruits and wine vinegar. 

7. Acetobacter oxydans (Henneberg, 
1897) Bergey et al., 1923. {Bacterium oxydans 
Henneberg, Cent. f. Bakt., II Abt., 3, 1897, 
223; Bergey et al.. Manual, 1st ed., 1923, 
36.) 

ox'y.dans. Gr. adj. oxys sharp; M.L. 
part. adj. oxydans oxidizing. 

Rods, 0.8 to 1.2 by 2.4 to 2.7 microns, 
occurring singly and in chains. Motile cells 
possess a single polar flagellum (Vaughn, 



Jour. Bact., 46, 1943, 394). The chains show 
bud-like swellings. 

Gelatin colonies: Circular, becoming 
irregular in shape with peculiar ramifica- 
tions. 

Minimum nutritional requirements: Pan- 
tothenic acid, nicotinic acid, p-amino- 
benzoic acid, valine, alanine, isoleucine, 
histidine, cystine, proline, mineral salts 
and an o.xidizable substrate such as alcohol, 
glucose, etc. (Foda and Vaughn, Jour. 
Bact., 65, 1953, 79). 

Acid from arabinose, fructose, glucose, 
galactose, sucrose, maltose, rafiinose, dex- 
trin, ethanol, propanol, erythritol, man- 
nitol, glycol or glycerol. No acid from 
sorbose, lactose, starch, gl3^cogen, inulin, 
methanol, isopropanol, butanol, isobutanol, 
pentanol, dulcitol or acetaldehyde (Hen- 
neberg, Die deutsch. Essigind., 2, 1898, 147). 

Optimum temperature, between 18° and 
21° C. 

Distinctive characters: Low optimum 
temperature for growth and oxidation of 
substrates; also the ability to oxidize a 
large number of substrates. 

Habitat: Beer, souring fruits, wine vine- 
gar. 



Genus IV. Aeromonas Kluyver and van Niel, 1936.* 
(Zent. f. Bakt., II Abt., 94, 1936, 398.) 

A.e.ro.mo'nas. Gr. mas.n. aer air, gas; Gr. fem.n. monas unit, monad; M.L. fem.n. 
Aeromonas gas (-producing) monad. 

Short (rarely more than 3 microns), rod-shaped cells. Motile by means of polar flagella, 
usually monotrichous; occasionally non-motile. Gram-negative. Heterotrophic, o.xidizing 
various organic compounds. Carbohydrates fermented with the production of Ho , CO2 and 
2,3-butylene glycol. Methyl red negative. Slow or no fermentation of lactose. The majority 
of species thus far described are from water or are known to be pathogenic to marine and 
fresh -water animals such as fish and amphibians. 

Physiologically these organisms appear to be identical with certain species found in the 
family Enter ohacteriaceae. The chief differences between the species in Aeromonas and those 
in Paracolobactrum Borman, Stuart and Wheeler are found in the arrangement of their 
flagella, in the less active fermentation of carbohydrates by the former, and in their patho- 
genicity. 

The type species is Aeromonas liquefaciens (Beijerinck) Kluyver and van Niel. 



Key to the species of genus Aeromonas. 

I. Motile. 

A. Originally isolated from water. 

* Prepared by Dr. S. F. Snieszko, U. S. Fish and Wildlife Service, Leetown via Kear- 
neysville, West Virginia, August, 1953. 



190 



ORDER I. PSEUDOMONADALES 



1. Not proven to be pathogenic for fish and amphibians. 

1. Aeromonas liquefaciens. 

2. Generally regarded as the cause of an infectious edema of carp and other fish. 

2. Aeromonas punctata. 
B. Originally isolated from a septicemia in frogs (red leg). 

3. Aeromonas hydrophila. 
II. Non-motile. Pathogenic for fish, particularly Salmonidae. 

4. Aeromonas salmonicida. 



1. Aeromonas liquefaciens (Beijerinck, 
1900) Kluyver and van Niel, 1936. {Aero- 
bacter liquefaciens Beijerinck, Cent. f. Bakt., 
II Abt., 6, 1900, 199; Kluyver and van Niel, 
Zent. f. Bakt., II Abt., 94, 1936, 399.) 

li.que.fa'ci.ens. L. v. liquefacio to 
liquefy; L. part. adj. liquefaciens liquefying. 

Description taken from Beijerinck (op. 
cit., 6, 1900, 199) and from E. M. Miles and 
A. A. Miles (Jour. Gen. Microbiol., 5, 1951, 
299). 

Rods, 0.4 to 0.8 by 1.5 to 3.0 microns, 
with parallel sides and rounded ends. Fila- 
ments common in "rough" colony forms. 
Motile by means of a single polar flagellum 
about 5 to 6 microns long. Gram-negative. 

Gelatin stab: Liquefaction marked and 
commonly saccate, good growth. 

Horse blood agar colonies: 2 to 3 mm in 
diameter, round, entire, raised, smooth, 
moist, opaque, semi-translucent, grayish 
white, forming a dirty brown-yellow colora- 
tion after 3 to 5 days at room temperature ; 
non-hemolytic. 

Broth: Growth abundant, turbid, with a 
moderate, readily disintegrable sediment 
and delicate pellicle. 

Loeffler's serum: Growth abundant, but 
no digestion. 

Litmus milk: Acid; coagulated; digested. 

Potato: Growth abundant, moist and 
glistening, light brown. 

Indole is produced. 

Nitrites but not ammonia produced from 
nitrates (Beijerinck); ammonia produced, 
presumably from peptones (Miles and 
Miles) . 

Methyl red test negative. 

Citric acid and salts of citric acid may be 
utilized as sole sources of carbon. 

Ammonium sulfate, uric acid and aspara- 
gine may be utilized as sources of nitrogen. 

Catalase produced. 

Hydrogen sulfide produced. 



Urea not attacked. 

Methylene blue reduced. 

Starch hydrolyzed (Miles and Miles) ; 
starch not hydrolyzed (Beijerinck). 

Acid and gas from glucose, galactose, 
fructose, mannose, maltose, sucrose, man- 
nitol, glycerol and starch. Acid from lactose, 
raffinose, inositol and sorbitol. Slight acid 
from salicin at 22° C. but none at 37° C. 
Glucose fermented with the production of 
2,3-butanediol. Arabinose, rhamnose and 
dulcitol not attacked. 

Aerobic, facultative. 

Temperature relations: Optimum, 37° C; 
good growth on ordinary laboratory media 
at 20° C. 

Produces a characteristic black-rot in 
hen eggs. 

Pathogenic to mice, also to frogs, causing 
a fatal bacteriemia. 

Source: Found rarely in canal mud, 
generally in certain marshes and swamps. 

Habitat relationships uncertain. Those 
that believe this organism to be identical 
with Aeromonas punctata would associate it 
with a disease of carp, eels and other fishes. 

2. Aeromonas punctata (Zimmermann, 
1890, emend. Lehmann and Neumann, 1896) 
Snieszko, comb. nov. (Bacillus punctatus 
Zimmermann, Bakt. unserer Trink- und 
Nutzwasser, Chemnitz, 1, 1890, 38; Bac- 
terium punctatum Lehmann and Neumann, 
Bakt. Diag., 1 Aufl., 2, 1896, 238; Pseudo- 
monas punctata Chester, Man. Determ. 
Bact., 1901, 147; also see Schaperclaus, 
Ztschr. f. Fischerei, 28, 1930, 289.) 

punc.ta'ta. L. noun punctum a point, a 
small hole; M.L. adj. punctata full of points. 

Rods, 0.7 by 1.0 to 1.5 microns, occurring 
singly, in pairs and in chains. Motile with 
a single polar flagellum. Gram-negative. 

Gelatin colonies: Small, circular, gray, 
erose to filamentous, punctiform. 



FAMILY IV. PSEUDOMONADACEAE 



191 



Gelatin stab: Crateriform liquefaction. 
No pellicle. 

Agar slant: Gray, smooth, filamentous. 

Broth: Turbid with delicate pellicle. 

Litmus milk: Acid; coagulated; pep- 
tonized. 

Potato: Brownish yellow to brownish 
red color. 

Indole is produced. 

Hydrogen sulfide is produced. 

Acid and gas from glucose broth (Leh- 
mann and Neumann, op. cit., 1896, 238). 

Aerobic, facultative. 

Optimum temperature, between 25° and 
30° C. 

Distinctive characters: There does not 
seem to be any real difference between this 
organism and Aeromonas liquefaciens Kluy- 
ver and van Niel. Schaperclaus (Fisch- 
krankheiten, Braunschweig, 1 Aufi., 1935, 
46; Ztschr. f. Fischerei, 37, 1939, 7) recog- 
nizes definite varieties of this species: 
some are non-pathogenic, others are patho- 
genic to carp, and still others are patho- 
genic to eels. 

Source: From Chemnitz tap water (Zim- 
mermann). Commonly found in water of 
the River Main (Lehmann and Neumann, 
op. cit., 238; also see op. cit., 7 Aufl., 2, 1927, 
47). 

Habitat: Found in water supplies, es- 
pecially those in which carp, eels and other 
fishes occur. Causes an infectious edema in 
carp (Cyprinus) (Schaperclaus, op. cit., 
1930, 289; see Zent. f. Bakt., II Abt., 105, 
1942, 49) and other fishes. 

3. Aeromonas hydrophila (Chester, 
1901) Stanier, 1943. {Bacillus htjdrophilus 
fuscus Sanarelli, Cent. f. Bakt., 9, 1891, 
222; Bacillus hydrophilus Chester, Manual 
Determ. Bact., 1901, 235; Proteus hydro- 
philus Bergey et al.. Manual, 1st ed., 1923, 
211; Stanier, Jour. Bact., 46, 1943, 213.) 

hy.dro'phi.la. Gr. noun hydor water; Gr. 
philus loving; M.L. adj. hydrophilus water- 
loving. 

Description taken from Emerson and 
Norris (Jour. Exp. Med., 7, 1905, 32) and 
from E. M. Miles and A. A. Miles (Jour. 
Gen. Microbiol., 5, 1951, 299). 

Rods, 0.6 by 1.3 microns, occurring singly 
and in chains. Motile, with a single polar 



flagellum (Kulp and Borden, Jour, of Bact., 
U, 1942, 673). Gram-negative. 

Gelatin colonies: Small, circular, gray, 
translucent, stippled. 

Gelatin stab: Napiform liquefaction. 

Agar colonies: Whitish, raised, moist, 
stippled. 

Horse blood agar colonies: 2 to 3 mm in 
diameter, round, entire, raised, smooth, 
moist, semi-translucent, grayish white, 
forming a dirty brown-yellow coloration 
after 3 to 5 days at room temperature; 
marked hemolysis. 

Agar slant : Thin, whitish, glassy, spread- 
ing, becoming yellowish and opalescent. 

Broth: Turbid, with heavy pellicle. 

Loeffler's serum: Growth abundant, but 
no digestion. 

Litmus milk: Acid; coagulated; pep- 
tonized. 

Potato: Yellowish brown, moist, slightly 
raised. 

Indole is produced. 

Nitrites produced from nitrates. 

Ammonium sulfate, uric acid and aspara- 
gine may serve as sources of nitrogen. 

Catalase produced. 

Hydrogen sulfide produced. 

Urea not attacked. 

Methylene blue reduced. 

Acid and gas from glucose, galactose, 
fructose, mannose, maltose, sucrose, man- 
nitol, glycerol and starch. Acid and gas 
from salicin at 22° C. but not at 37° C. Acid 
from glycogen and dextrin. Glucose fer- 
mented with the production of 2,3-butane- 
diol. Lactose, arabinose, raffinose, rham- 
nose, dulcitol, sorbitol and inositol not 
attacked. 

In the fermentation of beet molasses, 
Murphy, Watson, Muirhead and Barnwell 
(Canad. Jour. Tech., 29, 1951, 375) found 
this organism to yield up to 96 per cent of 
theoretical 2,3-butariediol and acetoin. 
This is a higher yield than the same authors 
found for Aerobacter aerogenes. 

Starch hydrolyzed. 

Gas ratio HjrCOs = 1:4.71. Methyl red 
negative, acetylmethylcarbinol positive, 
indole negative, citrate positive (Speck and 
Stark, Jour. Bact., U, 1942, 697). 

Aerobic, facultative. 

Optimum temperature, 37° C. 



192 



ORDER I. PSEUDOMONADALES 



Produces a characteristic black-rot in 
hen eggs. 

Pathogenic for frogs, salamanders, fish, 
mice, guinea pigs and rabbits, causing 
hemorrhagic septicemia. Causes a hemor- 
rhagic septicemia in snakes. In this case the 
disease is transmitted by mites (Camin, 
Jour, of Parasitol., 34, 1948, 345). 

Source: Isolated from frogs dead of 
septicemia (red leg). 

Habitat: Water and infected fresh-water 
animals. 

4. Aeroinonas salmonicida (Lehmann 
and Neumann, 1896) Griffin, 1954. (Bacillus 
der Forellenseuche, Emmerich and Weibel, 
Arch. f. Hyg.jBl, 1894, 1; Bacterium salmoni- 
cida Lehmann and Neumann, Bakt. Diag., 
1 Aufl., 2, 1896, 240; see Mackie, Arkwright, 
Pryce-Tannatt, Mottram, Johnston and 
Menzies, Final Rept. of the Furunculosis 
Committee, H. M. Stationery Office, Edin- 
burgh, 1935; Griffin, Trans. Amer. Fish. 
Soc, 83, (1953) 1954, 241.) 

sal.mo.ni'ci.da. L. noun salmo, salmonis 
salmon; L. v. suffix -cida from L. v. caedo to 
cut, kill; M.L. fem.n. salmonicida salmon- 
killer. 

Description taken from Griffin (Trans. 
Amer. Fish. Soc, 82 (1952) 1953, 129). 

Rods, 1.0 by 1.7 to 2.0 microns, with 
rounded ends, occurring singly, in pairs or 
in chains. Non-motile. Gram-negative. 

Gelatin stab: Crateriform to infundibuli- 
form liquefaction in 1 to 3 days; complete 
liquefaction in 7 days. Growth filiform, 
beaded, best at top. Medium turns light 
brown near the surface of old cultures. 

Agar colonies : Circular, punctiform in 24 
hours and 1 to 2 mm in diameter in 4 to 5 
days, convex, entire, semi-translucent. 
Colonies and medium turn brown in old 
cultures. 

Agar slant: Growth abundant, butyrous, 
glistening, filiform, opaque to transparent, 
odorless, colorless. A soluble, brown, me- 
lanin-like pigment forms in 3 to 5 days. 
A bright salmon-pink color develops when 
i8-2-thienylalanine is present (Griffin, 
Snieszko and Friddle, Jour. Bact., 65, 1953, 
658). 



Colonies developed on trypticase agar 
quickly turn a violet-black color after the 
addition of 1 per cent aqueous p-phenyl- 
enediamine (Griffin, Proc. 52nd Gen. Meet- 
ing, Soc. Ajner. Bact., Boston, 1952, 53; 
also see Vet. Med., 48, 1953, 280). 

Broth: Moderate to strong clouding; no 
ring or pellicle; moderate, flocculent sedi- 
ment. Medium may clear in the upper 
layers and some growth may adhere to walls 
of test tubes of old cultures. 

Litmus milk: Slight and temporary acidi- 
fication. Complete peptonization in one 
week. 

Rabbit blood agar: Beta-hemolysis in 2 
days. 

Indole not produced. 

Nitrites produced from nitrates. 

Ammonia produced in tryptic digest of 
casein-yeast extract medium. 

Hydrogen sulfide not produced. 

Methyl red negative; acetylmethylcarbi- 
nol not produced; sodium citrate does not 
serve as a sole source of carbon. 

Urea not attacked. 

Acid and gas from glucose, fructose, 
maltose, galactose, arabinose, mannose, 
starch, dextrin, glycogen, salicin, esculin 
and mannitol. Lactose, sucrose, xylose, 
rhamnose, trehalose, melibiose, cellobiose, 
raffinose, melizitose, inulin, amygdalin, 
methyl glucoside, glycerol, erythritol, 
adonitol, sorbitol and dulcitol not attacked. 

Starch hydrolyzed. 

Arginine and methionine are essential 
for growth; asparagine and leucine are 
highly stimulative while lysine is only 
moderately so (unpublished data, Griffin). 

Temperature relations: Optimum, be- 
tween 20° and 25° C. Minimum, 6° C. Maxi- 
mum, 34.5° C. 

Aerobic, facultative. 

Pathogenic for most fresh-water fish, 
particularly those belonging to Salmonidae. 

Source: From dead fish, of the family 
Salmonidae, taken from a fish hatchery in 
Southern Germany. 

Habitat: Found in fresh-water lakes, 
streams, rivers and fish ponds throughout 
Europe and also in the United States and 
Canada. Causes a furunculosis in infected 
fish; also occurs in apparently normal fish. 



FAMILY IV. PSEUDOMONADACEAE 193 

Note: Species incertae sedis. At least tons) is listed in the Manual as producing 

twelve additional species that appear to acid and gas from glucose and related 

be identical with or closely related to the sugars. A monographic studj' of these or- 

four species described in full have been ganisms is needed. The descriptions of some 

reported in the literature. These were isola- species that were found before 1900 appear 

ted from water, aquatic animals (midge to be as adequate as are the early descrip- 

larvae, leeches, fishes) or dairy products. tions of Aeromonas liquefaciens. No attempt 

It should also be noted that at least one has been made to determine which specific 

plant pathogen {Xanthomonas proteamacu- epithet or epithets have priority. 

Genus V. Photobacteriuni Beijerinck, 1889, emend. Breed and Lessel, 1954.* 

(Beijerinck, Arch, neerl. d. Sci. exact, et natur., 23, 1889, 401; Photobader Beijerinck, 
Troc. Sect. Sci., Kon. Akad. v. Wetensch., Amsterdam, 3, 1900, 352; ? Photomonas Orla- 
Jensen {nomen nudum). Jour. Bact., 6, 1921, 271; Breed and Lessel, Antonie van Leeuwen- 
hoek, 20, 1954, 60.) 

Pho.to.bac.te'ri.um. Gr. noun phos light; Gr. ueut.dim.n. bacterium a small rod; M.L. 
neut.n. Photobacterium light (-producing) bacterium. 

Coccobacilli and occasional rods which, in the presence of glucose and asparagine, tend to 
ramify in a manner analogous to that of bacteroids. Polar flagellate when motile. The type 
species is normally non-motile but shows motility in young cultures (Kluyver). May or may 
not liquefy gelatin. Produce acid, or acid and visible gas (H2 and CO2), from glucose and 
other carbohydrates but not from lactose. Luminescent. Growth and luminescence best, or 
even exclusively, on salt-water media containing 3 to 5 per cent salt. Found on dead fish 
and other salt-water animals and in sea water. Reports by various authors indicate that the 
luminescent^ coccoid and rod-shaped bacteria found living symbiotically in the tissues of 
the phosphorescent organs of various cephalopods and deep-sea fishes also belong to this 
genus. Other coccoid and rod-shaped luminescent bacteria found in the blood of Crustacea 
and caterpillars appear to be parasitic or even pathogenic. 

The type species is Photobacterium phosphoreum (Cohn) Ford. 

Key to the species of genus Photobacterium. t 

I. Coccobacilli which produce acid and gas from glucose. 

A. Saprophytic on dead fish, Crustacea, meat and similar products. 

1. Photobacterium phosphoreum. 

B. Symbiotic, found in the photogenic organ of a cephalopod. 

2. Photobacterium pierantonii . 
IL Short rods which produce acid but no gas from glucose. 

A. No growth at 37° C. 

3. Photobacterium fischeri. 

B. Grows well at 37° C. 

4. Photobacterium harveyi. 

1. Photobacterium phosphoreum fende het geneeskundig staatstoezicht in 

(Cohn, 1878) Ford, 1927. {Micrococcus Nederland, 1878, 126; Bacterium phos- 

phosphoreus Cohn, see letter addressed to phorescens Fischer, Cent. f. Bakt., 3, 1888, 

J. Penn, Verzameling van stukken betref- 107; Photobacterium phosphorescens Bei- 

* Prepared by Prof. Robert S. Breed and Mr. Erwin F. Lessel, Jr., Cornell University, 
Geneva, New York, February, 1954. 

t See Speucer (Jour. Gen. Microbiol., 13, 1955, 111) for a recent discussion of the classifica- 
tion of this group. 



194 



ORDER I. PSEUDOMONADALES 



jerinck, Arch, neerl. d. Sci. exact, et natur., 
£3, 1889, 401; Photobacter phosphoreum 
Beijerinck, Folia Microbiologica, Delft, 
4, 1916, 15; Ford, Textb. of Bact., 1927, 
615.) 

phos.pho're.um. Gr. v. phosphor eo to 
bring light; M.L. adj. phosphoreus light- 
bearing. 

Description taken from Fischer (op. cit., 
1888, 107) and Beijerinck {op. cit., 1889, 
401). 

Coccobacilli, 0.5 to 2.0 microns; oc- 
casional rods are 0.5 to 1.0 micron. In the 
presence of glucose, especially glucose and 
asparagine combined, some of the cells tend 
to branch and to take the form of bac- 
teroids. Frequently occur as zoogloeae. 
Non-motile (Fischer); some cells show a 
sluggish motility (Beijerinck); (Johnson, 
personal communication, 1953, stated that 
even electron micrographs failed to reveal 
flagella) ; actively motile on suitable media 
(Kluyver, personal communication, June, 
1953) ; Leifson (personal communication, 
July, 1953) reports that an occasional cell 
of culture L342 from Delft shows mono- 
trichous flagellation. Stain lightly with 
aniline dyes. Gram-negative (Manual, 3rd 
ed., 1930, 178). 

Gelatin: No liquefaction. 

Agar slant: Grayish white layer (Manual, 
loc. cit.). 

Broth: Slightly turbid with thin pellicle 
(Manual, loc. cit.). 

Potato: Ordinary acid potato, no growth; 
neutralized with sodium phosphate, thin 
brownish growth (Chester, Ann. Rept. Del. 
Col. Agr. Exp. Sta., 9, 1897, 124). 

Proteolytic enzymes not secreted. 

Glucose, fructose, maltose and galactose 
are anaerobically fermented with the pro- 
duction of gas. This is a butanediol fermen- 
tation that produces H2 and CO2 (Kluyver, 
personal communication, 1953). 

Aerobic, facultatively anaerobic. 

Minimum temperature, between 5° and 
10° C. 

Quality of luminescence: Bluish green. 

Salt tolerance: To assure phosphorescence 
and good growth, the osmotic tension of 
inorganic salt solutions used for cultivation 
should be equivalent to that produced in a 
3 per cent sodium chloride solution. 



Distinctive characters: Coccoid bacteria 
which do not liquefy gelatin and which 
produce acid and gas from glucose but not 
from lactose. In the presence of glucose, 
especially when combined with asparagine, 
the cells swell up greatly and lose their 
luminescent property. Luminescence on 
organic matter occurs only when there is a 
sufficient proportion of inorganic salt. 

Comments: Several publications which 
antedate that of Fischer (op. cit., 1888, 107) 
allude to the fact that the binomial Bac- 
terium phosphorescens might have been 
effectively published earlier than 1888. One 
reference (Anonymous, Nature, 35, 1886- 
1887, 377) cites Hermes, the Director of the 
Berlin Aquarium, as having published an 
article in which he describes and names as 
Bacteriian phosphorescens a luminescent 
organism obtained from a specimen of cod 
(Gadus callarias) at the Berlin Aquarium; 
this was the same organism which Fischer 
secured from the Berlin Aquarium and 
which he named Bacterium phosphorescens. 
A second reference (Ludwig, Cent. f. Bakt., 
2, 1887, 404) states that Hermes demon- 
strated before the Berlin Society the phos- 
phorescent bacterium from the Berlin 
Aquarium under the name Bacterium phos- 
phorescens. Other references (Anonymous, 
Gesell. deutsch. Naturforsch. u. Aerzte, 
Tageblatt, 60, 1887, 77 and 254) showed 
that Hermes used this organism several 
times for demonstration purposes in the 
Aquarium and before the Society. As 
Hermes' publication has not been found, and 
as the binomial Bacterium phosphorescens is 
not effectively published in anj- of the three 
references given directly above, Fischer is 
credited here as the author of this binomial. 

Considerable confusion exists in the 
literature concerning this species, most of 
which can be elucidated by the following: 
(1) Fischer (Ztschr. f. Hyg., 2, 1887, 54-92) 
described an organism, isolated from sea 
water from the West Indies, which he named 
Bacillus phosphorescens; (2) a second species 
of phosphorescent bacteria, obtained from 
the Berlin Aquarium, was described, but 
not named, by Fischer in a supplement to 
the work cited above (ibid., 92-95); Leh- 
mann (Cent. f. Bakt., 5, 1889, 785) also 
described an organism obtained from the 



FAMILY IV. PSEUDOMONADACEAE 



195 



Berlin Aquarium, and he states that it is 
identical with the one which Fischer ob- 
tained from this same source; (3) in a later 
paper (Cent. f. Bakt., S, 1888, 107), Fischer 
identified the second species, as well as 
phosphorescent bacteria that he isolated 
from dead fish from the Baltic and North 
Seas, as Bacterium phosphorescens. Some 
authors, e.g. Lehmann and Neumann (Bakt. 
Diag., 1 Aufl., 2, 1896, 198; and other edi- 
tions), Migula (Syst. d. Bakt., 2, 1900, 433) 
and Chester (Man. Determ. Bact., 1901, 
181), when referring to Bacterium phos- 
phorescens Fischer, quote the supplement 
to Fischer's paper in the Ztschr. f. Hyg., 2, 
1887, 92, as the source of the name Bacterium 
phosphorescens, whereas the first use of this 
binomial by Fischer was in the Cent. f. 
Bakt., 3, 1888, 107. This failure to give an 
exact reference has caused confusion in 
later publications, especially since Bacillus 
phosphorescens is the only binomial pro- 
posed, or even used, by Fischer in his paper 
published in the Ztschr. f. Hyg., 2, 1887, 
54-95, which also contains a description of 
the organism he later identified as Bacterium 
phosphorescens. Still other writers (Gorham, 
in Dahlgren, Jour. Franklin Inst., 180, 1915, 
517 and insert following 714) have used the 
name Bacillus phosphorescens in lieu of 
Bacterium phosphorescens, thus augmenting 
the confusion. 

Relationships to other species of bacteria: 
Beijerinck regards Photobacterium phos- 
phorescens Beijerinck as identical with 
Micrococcus phosphoreus Cohn (Folia Micro- 
biologica, Delft, 4, 1916, 15, footnote 4) 
but different from Photobacterium pfleugeri 
Ludwig (Arch, neerl. d. Sci. exact, et natur., 
24, 1891, 369). 

Source: Isolated from cod (Gadus cal- 
larias) from the Baltic Sea; also found on 
haddock {Melanogrammus aeglifinus) and on 
lobster (Homarus sp.). 

Habitat: Found on dead fish and in sea 
water, so far as known. 

2. Photobacterium pierantonii (Zir- 
polo, 1918) Krassilnikov, 1949. {Micrococcus 
pierantonii Zirpolo, Boll. del. Societa dei 
Natural, in Napoli, 31, (1918) 1919, 75; 
Photobacterium pierantonii, incorrectly 
ascribed to Bergey et al. by Krassilnikov, 



Guide to the Bacteria and Actinomycetes, 
Izd. Akad. Nauk, U.S.S.R., Moskau, 1949, 
514.) 

pie.ran.to'ni.i. M.L. gen. noun pier- 
antonii of Pierantoni; named for Prof. U. 
Pierantoni, an Italian scientist. 

Original description supplemented by 
material taken from Meissner (Cent. f. 
Bakt., II Abt., 67, 1926, 204). 

Cocci, 0.8 micron in diameter, and short 
rods, 0.8 by 1.0 to 2.0 microns. Occasionally 
vacuolated. Motile or non-motile, the 
motile cells possessing a single flagellum or 
a tuft of 2 to 4 flagella. Gram-negative. 

Gelatin colonies: Circular, luminous. 

Gelatin stab: No liquefaction. 

Sepia agar colonies: Circular, white, 
convex, smooth and serrate with an intense, 
greenish luminescence. 

Egg glj'cerol agar slant: Yellowish green, 
luminous streak. 

Broth: Turbid. 

Indole not produced. 

Acid and gas from glucose and maltose. 
Some strains produce acid but no gas from 
lactose and sucrose. 

Aerobic. 

Optimum temperature, 33° C. 

Optimum pH for growth, 9.0. No growth 
at pH 5.0. 

Optimum pH for luminescence, 8.0. No 
luminescence at pH 5.0. 

Quality of luminescence: Greenish. 

Source: Isolated from the photogenic 
organ of the cephalopod Rondeletia minor. 

Habitat: Apparently found only in 
Rondeletia minor but may also be found in 
closely related species. 

3. Photobacterium fischeri Beijerinck, 
1889. (Einheimischer Leuchtbacillus, Fis- 
cher, Cent. f. Bakt., 3, 1888, 107; Beijerinck, 
Arch, nderl. d. Sci. exact, et natur., 23, 1889, 
401; Vibrio fischeri Lehmann and Neumann, 
Bakt. Diag., 1 Aufl., 2, 1896, 342; Achromo- 
bacter fischeri Bergey et al.. Manual, 3rd ed., 
1930, 220.) 

fisch'er.i. M.L. gen. noun ^sc^e/z of Fis- 
cher; named for Prof. Bernhard Fischer, 
one of the earliest students of luminescent 
bacteria. 

Description taken from Fischer (op. cit., 
1888, 107), Beijerinck (op. cit., 1889, 401) and 



196 



ORDER I. PSEUDOMONADALES 



Johnson and Shiink (Jour. Bact., 31, 1936, 
589). 

Short, thick rods, 0.4 to 0.8 by 1.0 to 2.5 
microns, with rounded ends, occurring 
singly and in pairs. Occasional rods slightly 
curved, ends slightly pointed. Not encap- 
sulated. Motile. Johnson, Zworykin and 
Warren (Jour. Bact., 46, 1943, 167) made 
pictures with the electron microscope of 
a culture which they identified with this 
species; the organism showed a tuft of polar 
flagella. Gram-negative. 

Sea-water gelatin colonies : After 48 hours, 
colonies small (less than 0.5 mm in diam- 
eter), circular, entire, homogeneous, with 
slight liquefaction. 

Sea-water gelatin stab: Slight, infundi- 
buliform liquefaction, sometimes slightly 
beaded, tending to become crateriform in 
old cultures. 

Nutrient sea-water agar colonies: Small, 
circular, smooth, entire, slightly raised, 
homogeneous, iridescent. Old colonies be- 
come yellowish with margins slightly ser- 
rate. 

Sea-water agar slant: Growth abundant, 
grayish to jellowish, smooth, viscous, 
homogeneous, iridescent. 

Growth on autoclaved fish: Moderate, 
grayish to yellowish, smooth, glistening, 
luminescent, no odor of putrefaction. 

Sea water containing 0.2 per cent peptone : 
Moderate growth, mostly near the surface; 
very thin pellicle; sediment found in old 
tubes. 

Milk: No growth. Milk with 2.8 per cent 
sodium chloride : Slight growth and lumines- 
cence, but no action on the milk. 

Potato plugs resting on cotton saturated 
in sea water: Growth fairly abundant, 
spreading, slightly brownish, luminous. 

Blood serum: No growth. 

Indole not produced. 

Hydrogen sulfide is produced. 

Acid but no gas from glucose (Gorham, 
in Dahlgren, Jour. Franklin Inst., 180, 
1915, 517 and insert following 714). Acid 
from glycerol, fructose, galactose, mannose, 
maltose, cellobiose, dextrin and salicin. 
No acid or gas from lactose, sucrose, arabi- 
nose, xylose, fucose, rhamnose, trehalose, 
raffinose, glycogen, inulin, adonitol, dulci- 



tol, inositol, sorbitol, erythritol, arabitol 
or alpha-methyl-glycoside. 

Starch hydrolysis is doubtful or verj' 
slight. 

Decarboxjlates glutamic acid to form 
7-aminobutyric acid and CO2 ; decarboxjd- 
ates lysine (Pearson, Jour. Cell, and Comp. 
Physiol., 41, 1953, 65). 

Alanine, arginine, aspartic acid, glutamic 
acid and threonine are capable of serving 
as sole nitrogen sources for this organism 
(Pearson, Jour. Tenn. Acad. Sci., 27, 1952, 
229). 

Nitrites produced from nitrates. 

Ammonia produced in peptone media. 

Aerobic, facultatively anaerobic. 

Temperature relations: Optimum, be- 
tween 25° and 28° C. Minimum, between 5° 
and 10° C. No growth at 37° C. 

Optimum temperature for luminescence, 
28° C. Weak at 10° C., none at 5° nor at 37° C. 

Optimum pH for luminescence, between 
7.4 and 7.8; less intense at 7.0 and 8.2. 
Fischer (Erg. d. Plankton Expedition d. 
Humboldt-Stiftung, 4, 1894) noted that 
this organism grows best in alkaline rnedia. 

Quality of luminescence: Orangish, main- 
tained for 5 to 8 weeks (Beijerinck); green- 
ish (Johnson and Shunk). Luminescence 
favored by the presence of glycerol in the 
medium. 

Salt tolerance: The osmotic tension of 
inorganic salt solutions used as media for 
this species must be equivalent to that 
produced in a 2.8 to 3.0 per cent sodium 
chloride solution to assure luminescence and 
good growth. 

Not pathogenic for white rats. 

Distinctive character: Luminescence on 
organic matter occurs only when there is a 
suflftcient proportion of inorganic salt pres- 
ent. 

Source: Isolated from sea water at Kiel 
and from herring. 

Habitat: Frequentlj^ found on dead fish, 
Crustacea and other salt-water animals and 
in coastal sea water. Phosphorescent bac- 
teria also occur on meat and even on sol- 
dier's wounds where they produce no known 
harmful effects. No food poisoning has been 
traced to meat on which these organisms 
have grown (Niven, Circular No. 2, Ameri- 
can Meat Inst. Foundation, 1951, 1-11). 



FAMILY IV. PSEUDOMONADACEAE 



197 



4. Photobacteriuni harveyi (Johnson 
and Shunk, 1936) Breed and Lessel, 1954. 
(Achro)nobacter harveyi Johnson and Shunk, 
Jour. Bact., 31, 1936, 587; Breed and Lessel, 
Antonie van Leeuwenhoek, 20, 1954, 61.) 

har'vey.i. M.L. gen. noun harveyi of 
Harvey; named for E. N. HarveJ^ 

Description taken from Johnson and 
Shunk (op. cif., 1936, 587). 

Rods, .0.5 to 1.0 by 1.2 to 2.5 microns, 
occurring singly or in pairs, with rounded 
ends. Occasionally slightly curved; ends 
occasionally slightly pointed. Non-spore- 
forming. Not encapsulated. Motile by 
means of a single, polar flagellum 2 to 3 
times the length of the cell. Gram-negative. 

Sea-water gelatin colonies: After 24 
hours at 20° C, circular, about 1.5 mm in 
diameter or larger, margin slightly undu- 
late, sunken due to the beginning of lique- 
faction, interior somewhat zonate; colonies 
surrounded by a halo of numerous small 
secondary colonies, circular and finely 
granular. In crowded plates a large number 
of gas bubbles are formed. Luminescent. 

Sea-water gelatin stab: Rapid saccate 
liquefaction complete in 5 daj^s at 22° C. 
Abundant flocculent sediment. 

Sea-water agar colonies: Mostly very 
large, 6 to 8 cm in diameter in 24 hours, flat, 
highly iridescent, circular with undulate 
margin, or composed of narrow and close or 
wide filamentous growth. Occasionally 
small colonies appear that are circular, with 
entire or slightly undulate margin, often 
producing irregular secondary growth, sur- 
face always smooth. Luminescent. 

Sea-water agar slant: Growth abundant, 
spreading, grayishly viscous, homogeneous, 
iridescent, the medium becoming rapidly 
alkaline w^hen inoculated at an initial pH 
of 7.0. With fish decoctions added to the 
medium, luminescence is much brighter 
and growth becomes brownish after several 
days. 

Growth on autoclaved fish: Abundant, 
smooth, glistening, yellowish, becoming 
dirty brown after several days. Mild putre- 
factive odor. Luminescence very brilliant. 

Sea water containing 0.2 per cent peptone : 
Abundant uniform turbidity, thin pellicle, 
sediment accumulating over a period of 



several days. Luminescence at surface only 
unless the tube is shaken. 

Milk, with or without the addition of 2.8 
per cent salt: No growth. 

Potato plugs resting on cotton saturated 
with sea water: Growth slight, somewhat 
spreading, slightly brownish. Luminous. 

Indole produced (Gore's method). 

Hydrogen sulfide is produced (ZoBell 
and Fantham method). 

Fixed acid from glucose, fructose, man- 
nose, galactose, sucrose, maltose, mannitol, 
dextrin, glycogen, trehalose, cellobiose; 
slowly from salicin. Non-fixed acid from 
melezitose; slight acid from sorbitol, disap- 
pearing in 24 hours. No acid from glycerol, 
xylose, arabinose, dulcitol, inositol, adoni- 
tol, erythritol, arabitol, lactose, raffinose, 
rhamnose, fucose or alpha methyl glucoside. 

Starch agar: Wide zone of hydrolysis. 

Nitrites produced from nitrates. 

Ammonia produced in peptone media 
(Hansen method). 

Aerobic, facultatively anaerobic. 

Temperature relations: Optimum, be- 
tween 35° and 39° C. Abundant growth be- 
tween 22° and 25° C. 

Optimum temperature for luminescence, 
between 20° and 40° C. 

Optimum pH for luminescence, between 
pH 7.4 and 7.8. 

Quality of luminescence (to completely 
dark-adapted eyes) : Yellowish green to 
green on fish and typically green on sea- 
water agar or gelatin. 

Not pathogenic for white rats or amphi- 
pods. 

Distinctive character: Luminescence not 
favored by the presence of glycerol in the 
medium. 

Source: Isolated from a dead amphipod 
(Talorchesda sp.) at Woods Hole, Massa- 
chusetts. 

Habitat: Sea water. 

Note: Species incertae sedis. Additional 
luminescent bacteria which probably be- 
long in this genus have been reported in 
the literature. However many of the de- 
scriptions are not adequate enough to 
permit the determination of the identity 
and relationships of these organisms. 



ORDER I. PSEUDOMONADALES 



Genus VI. Azotonionas Stapp, 1940.* 

(Stapp, Zent. f. Bakt., II Abt., 102, 1940, 18; not Azotomonas Orla-Jensen, 
Cent. f. Bakt., II Abt., U, 1909, 484.) 

A.zo.to.mo'nas. Gr. azous without life; Fr. noun azote nitrogen; Gr. fem.n. monas unit, 
monad; M.L. fem.n. Azotomonas nitrogen (-fixing) monad. 

Rod- to coccus-shaped cells. Motile by means of 1 to 3 polar fiagella. No fat-like reserve 
food granules in the cells. Chemo-heterotrophic. Produce acid and sometimes gas from glu- 
cose and other sugars and alcohols. Many carbon compounds other than sugars are used as 
sources of energj-. Indole is produced. Aerobic. Active in the fixation of atmospheric nitro- 
gen. Found in soil. 

The type species is Azotomonas insolita Stapp. 

Key to the species of genus Azotonionas. 
I. Acid and gas from glucose. 



II. Acid but no gas from glucose. 



1. Azotomonas insolita. 

2. Azotomonas fluorescens. 



1. Azotomonas insolita Stapp, 1940. 
(Abstracts of Communications, Third In- 
ternat. Congr. for Microbiol., Sect. VIII, 
1939, 306; abst. in Proc. Soil Sci. Soc. of 
America, 4, 1939, 244; Zent. f. Bakt., II 
Abt., 102, 1940, 1.) 

in.so'li.ta. L. adj. insolitus unusual. 

Coccoid rods 0.6 to 1.2 by 0.6 to 1.8 mi- 
crons. Motile by means of 1 to 3 polar 
flagella. Gram-negative. 

Gelatin: No liquefaction. 

Agar colonies: Flat, whitish, entire, 
weakly fluorescent. 

Agar slant: Glistening, white growth. 

Broth: Strongly turbid; sediment; pel- 
licle. 

Milk: Unchanged. 

Potato: Growth somewhat dry, not slimy, 
dirty gray, spreading. 

Hydrogen sulfide is produced. 

Acid and gas from adonitol, arabinose, 
dextrin, glucose, galactose, glycerol, 
inositol, lactose, fructose, maltose, man- 
nose, mannitol, raffinose, rhamnose, salicin, 
sorbitol, starch, sucrose and xylose. 

Starch is hydrolyzed. 

Nitrites produced from nitrates. 

Atmospheric nitrogen is fixed. 

Ammonium salts are utilized. 

Aerobic. 

Temperature relations: Optimum, be- 
tween 25° and 30° C. Minimum, between 



7.0° and 9.5° C. Maximum, 48° C. Good 
growth at 37° C. Thermal death point, 
60° C. 

Limits of pH, 3.3 to 9.5. 

Source: Isolated from a mixture of chop- 
ped cotton husks and rice hulls. 

Habitat: Soil. 

2. Azotonionas fluorescens Krassilni- 

kov, 1947. (Quoted from Krassilnikov, Guide 
to the Bacteria and Actinomycetes, Izd. 
Akad. Nauk, U.S.S.R., Moskau, 1949, 420.) 

flu.o.res'cens. L. noun fluor a flux; M.L. 
v. fluoresco to fluoresce; fluor-spar, a flux- 
ing mineral which is fluorescent; M.L. 
part. adj. fluorescens fluorescing. 

Translated by Dr. A. Petraitis, New York 
State Experiment Station, Geneva, New- 
York. 

Rod-shaped cells, 0.5 to 0.8 by 2.0 to 5.0 
microns, which become shorter in old cul- 
tures. Motile by means of one to three 
polar flagella. Gram-negative. 

Gelatin: Slow liquefaction. 

Inorganic media with or without nitro- 
gen: Good growth. 

Colonies are wide, smooth and glistening. 

A slightly yellowish or violet fluorescent 
pigment is produced which diffuses through 
the medium. 

Milk: Peptonized. 



* Rearranged by Dr. A. W. Hofer, New York State Experiment Station, Cornell Univer- 
sity, Geneva, New York, November, 1953. 



FAMILY IV. PSEUDOMONADACEAE 



199 



Acid but no gas from various sugars and 
alcohols. 

Starch is hj'drolyzed. 
Fixes nitrogen. 



Nitrites not produced from nitrates. 

Aerobic. 

Source: Isolated from soil. 

Habitat: Soil. 



Genus VII. Zymomonas Kluyver and van Niel, 1936* 

(Kluj'ver and van Niel, Zent. f. Bakt., II Abt., H, 1936, 399; Saccharomonas 
Shimwell, Jour. Inst. Brewing, 56 (N.S. 47), 1950, 179.) 

Zy.mo'mo.nas or Zy.mo.mo'nas. Gr. noun zyme leaven, ferment; Gr. noun monas a 
unit, monad; M.L. fem.n. Zymomonas fermenting monad. 

Rod-shaped cells, occasionally ellipsoidal. Motile cells are lophotrichous. Anaerobically 
ferment glucose with the production of carbon dioxide, ethyl alcohol and some lactic acid. 
Found in fermenting beverages such as pulque, palm juice and beer. 

The type species is Zymomonas mobilis (Lindner) Kluyver and van Niel. 



1. Zymomonas mobilis (Lindner, 1928) 
Kluyver and van Niel, 1936. (Termobac- 
terium mobile Lindner, Atlas d. Mikrosk 
Grundl. d. Garungsk., 3 Aufl., 2, 1928, Taf 
68; also see Lindner, 50 Jubilaumsber 
Westpreuss. Bot.-Zool. Vereins, 1928, 253 
Pseudomonas lindneri Kluyver and Hoppen 
brouwers, Arch. f. Mikrobiol., £, 1931, 259 
Zymomonas mobile (sic), Kluyver and van 
Niel, Zent. f. Bakt., II Abt., 94, 1936, 399 
Saccharomonas lindneri Shimwell, Jour. 
Inst. Brewing, 56 (N. S. 47), 1950, 179.) 

mo'bi.lis. L. adj. mobilis movable, motile. 

Short rods with rounded ends, 1.4 to 2.0 
by 4.0 to 5.0 microns. Occur usually as pairs 
with a central constriction and rarely as 
short chains. Motile with polar flagella. 
Gram-negative. 

Peptone gelatin: Poor growth. 

Peptone agar: Poor growth. 

Wort agar: White, round, raised colonies 
1 mm in diameter. Good growth. Still better 
growth where 2 per cent sucrose or yeast 
extract with sucrose is added. Chalk may be 
added to neutralize acid. 

Wort gelatin stab: Uniform growth in 
stab; no surface growth. No liquefaction. 

Broth: Poor growth in peptone or yeast 
extract broth unless sugars are added. 

Carbon dioxide, ethyl alcohol and some 
lactic acid produced from glucose and 
fructose but not from mannose. Ferments 
sucrose usually after a somewhat prolonged 
lag period. May produce as much as 10 per 
cent alcohol. 

Catalase-positive. 



Anaerobic, although with a certain 
oxygen tolerance of aerobic growth in the 
presence of fermentable sugars. 

Optimum temperature, 30° C. 

Distinctive character: Apart from the 
production of some lactic acid, the fermen- 
tation resembles the alcoholic fermentation 
produced by j'easts. 

Source : Isolated from the fermenting sap 
(pulque) of Agave americana in Mexico and 
from fermenting palm juice {Arenga sac- 
charifera) in Sumatra and Java (Roelofsen, 
Natuurwetenschappelijk Tijdschrift voor 
Ned-. Indie, 101, 1941, 374). 

Habitat: Found in fermenting plant 
juices in tropical countries (Mexico and 
Indonesia). 

2. Zymomonas anaerobia (Shimwell, 
1937) Kluyver, comb. nov. (Achromobacier 
anaerobium Shimwell, Jour. Inst. Brewing, 
43, 1937, 507; Saccharomonas anaerobia Shim- 
well, op. cit., 56 (N. S. 47), 1950, 179 (type 
species of genus Saccharomonas Shimwell).) 

an.a.e.ro'bi.a. Gr. pref. an not; Gr. 
noun aer air; Gr. noun bins life; M.L. adj. 
anaerobius not living in air. 

Rods, 1.0 to 1.5 by 2.0 to 3.0 microns, 
plump with rounded ends. Cells occasionally 
clump together to form rosette-like clusters. 
Young cells actively motile with lophotri- 
chous flagella, old cells become non-motile. 
Not encapsulated. Gram-negative. 

Glucose-beer-gelatin stab: Dense, fili- 
form to beaded growth in stab; no surface 
growth. No liquefaction. 



* Prepared by Prof. A. J. Kluyver, Technische Hogeschool, Delft, Holland, December, 
1953. 



200 



ORDER I. PSEUDOMONADALES 



Glucose-beer-agar colonies: When in- 
cubated in CO2 , irregularly circular, entire, 
convex, about 1 mm in diameter, cream- 
colored by reflected light, brown by trans- 
mitted light, thinly butyrous, granular. 

Glucose-beer-agar slant: Normally there 
is no growth although there may be a slight 
growth after prolonged incubation. Fili- 
form or beaded, creamy white, thinly 
butyrous, non-adherent growth when incu- 
bated in CO2 . 

Glucose-beer-agar stab: Dense, filiform 
to beaded growth in stab; no surface growth. 

Yeast extract, sugar-free beer: No 
growth. 

Beer, 2 per cent glucose: Densely turbid, 
later becoming clear with a heavy sediment. 

Yeast extract glucose broth: Growth only 
in deep medium; slight deposit on walls of 
tube; dense sediment at bottom. 

Indole not produced. 

Glucose and fructose readily fermented; 
maltose, sucrose, lactose and ethyl alcohol 
not attacked. 

Acetylmethylcarbinol and diacetyl not 
produced. 

Nitrites not produced from nitrates. 

Anaerobic, microaeroduric (not micro- 
aerophilic) . 



Temperature relations: Optimum, 30° C.; 
thermal death point, 60° C. for 5 minutes. 

pH range for growth, 3.4 to 7.5. 

Distinctive characters: Does not grow in 
any medium unless glucose or fructose is 
present. 8himwell {loc. cit.) recognizes a 
non-motile variety of this species. A related 
or perhaps identical species has been de- 
scribed as the cause of "cider sickness" in 
England (see Barker, Ann. Rept. Nat. 
Fruit and Cider Inst. Long Ashton, 1948). 

A comparative study of cultures of Zymo- 
monas mobilis, Z. anaerobia and the cider 
organism made in 1951 shows that these 
organisms are closely related. Z. anaerobia 
did show fermentation of sucrose although 
the cider organism did not show this fer- 
mentation (Kluyver, personal communica- 
tion). 

Source: Isolated from beer, from the 
surface of brewery yards and from the 
brushes of cask-washing machines. 

Habitat: Plant juices or extracts con- 
taining glucose. 

Note: Species incertae sedis. Additional 
species which probably belong in this genus 
but which have not been well described have 
been reported from beer and cider. 



Genus VIII. Protaminobacter den Dooren de Jong, 1926 * 

(Bijdrage tot de kennis van het mineralisatieproces. Thesis, Rotterdam, 1926, 159.) 

Pro.ta.mi.no.bac'ter. Gr. sup.adj. protus first; M.L. noun aminum an amine; M.L. 

mas.n. bacter masculine form of Gr. neut.n. bactrum rod or staff; M.L. mas.n. Protaminobacter 

protamine rod. 

Cells motile or non-motile. Capable of dissimilating alkylamines. Pigmentation frequent. 
Soil or water forms. 

Recently Slepecky and Doetsch (Bact. Proc, 54th Gen. Meeting, Soc. of Amer. Bact., 
1954, 44) have isolated 23 fresh cultures of polar flagellate organisms that utilize alkyl- 
amines. Of these, one resembled a known species of Protaminobacter, but all showed the 
general characters of organisms placed in the genus Pseudomonas. The authors question 
the recognition of the genus Protaminobacter on a biochemical basis only. 
The type species is Protaminobacter albofiavus den Dooren de Jong. 



Key to the species of genus Protaminobacter. 

I. Non-motile. Gelatin colonies light yellow to colorless. 

1. Protaminobacter albofiavus. 
II. Motile. Gelatin colonies red. 

2. Protaminobacter ruber. 

* Prepared by Prof. D. H. Bergey, Philadelphia, Pennsylvania, June, 1929; further re- 
vision by Prof. Robert S. Breed, New York State Experiment Station, Geneva, New York, 
July, 1953. 



FAMILY IV. PSEUDOMONADACEAE 



201 



1. Protaminobacter alboflavus den 

Dooren de Jong, 1926. (Thesis, Rotterdam, 
1926, 159; also see Cent. f. Bakt., II Abt., 
71, 1927, 218.) 

al.bo.fla'vus. L. adj. alhus white; L. 
adj. flavus j-ellow; M.L. adj. alboflavus 
whitish yellow. 

Rods. Non-motile. Gram-negative. 

Gelatin colonies: Circular, dry, light 
yellow or colorless. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular, opaque, pigment 
bright red, yellow, light gray or colorless. 

Amine agar colonies: Circular, white to 
dark yellow. 

See Table I for list of organic substances 
utilized. 

Catalase produced. 

Aerobic, facultative. 

Optimum temperature, 30° C. 

Distinctive characters : The author recog- 
nizes four varieties of this species which he 
differentiates on the basis of organic sub- 
stances attacked (see Table) and pigment 
produced. Variety a shows light yellow 
growth on gelatin, bright red on agar and 
yellow on amine agar. Variety' /3 is light 3'el- 
low on gelatin, yellow on agar and dark 
yellow on amine agar. Variety y is light 
yellow on gelatin, light gray on agar and 
yellow on amine agar. Variety 5 is colorless 
on gelatin and agar and white on amine 
agar. 

Habitat: Soil and water. 

2. Protaminobacter ruber den Dooren 
de Jong, 1926. (Thesis, Rotterdam, 1926, 
159; also see Cent. f. Bakt., II Abt., 71, 1927, 
218.) 

ru'ber. L. ruber red. 

Rods. Motile with a single polar flagellum 
(Weaver, Samuels and Sherago, Jour. Bact., 
35, 1938, 59). Gram-negative. 

Gelatin colonies: Circular, red, dry. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular, red, opaque. 

Amine agar colonies: Circular, dark red. 

The following organic acids are attacked: 
Acetic, lactic, |3-oxybutyric, glycerinic, 
succinic, malonic, formic, methyl formic, 
glutaric, maleinic, fumaric, malic, tartaric, 
citric and quinic. 

The following amino compounds are 



Table I. — Organic Substances Utilized as a 

Source of Carbon by Varieties (biotypes) of 

Protaminobacter alboflavus 



Organic acids: 

Acetic 

Valerianic 

a-crotonic 

Undecyclic 

Lactic 

/3-oxybutyric 

Succinic 

Formic 

Glutaric 

Adipic 

Fumaric 

Malic 

Tartaric 

Citric 

/3-phenj'lpropionic 

Quinic 

Amino compounds: 

a-alanin 

a-aminocapronic acid 

Leucin 

Propionamid 

Capronamid 

Uric acid 

Hippuric acid 

Alcohol : 
Ethyl 

Sugar : 
Glucose 

Amines : 

Ethyl 

Diethyl 

Propyl 

Isopropyl 

Dipropyl 

Tripropyl 

Butyl 

Isobutyl 

Diisobutyl 

Amyl 

Diamyl 

Ethanol 

Glucosamin 

Benzyl 



« 





7 


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+ 



202 ORDER I. PSEUDOMONADALES 

attacked: Sarcosiu, betain, hippuric acid, Catalase produced, 

asparagine, propionamid, capronamid, lac- Aerobic, facultative, 

tainid, succinamid, allantoin and uric acid. Optimum temperature, 30° C. 

Glucose fermented. Habitat: Soil and v/ater. 

Genus IX. Alginomonas Thj^tta and Kdss, 1945.* 

(Thj0tta and K&ss, Norske Videnskaps-Akad., Oslo, I Mat.- Naturv. Klasse, No. 5, 1945, 
17; also see lass. Lid and MoUand, ibid., No. 11, 1945, 8.) 

Al. gi.no. mo 'nas. L. fem.n. alga seaweed; M.L. adj. alginicus pertaining to alginic acid 
from seaweed; Gr. noun nionas a unit, monad; M.L. fem.n. Alginomonas alginic-acid (-de- 
composing) monad. 

Coccoid rods which are motile with one to four polar fiagella. Gram-negative. Fluorescent. 
Gelatin is usually liquefied. Carbohydrates are not utilized. Citric acid is not used as a sole 
source of carbon. Alginic acid is decomposed. Found on algae and in sea water and soil. 

As the type of flagellation has not been determined for all of the species here included in 
the genus, it may be found later that some of these species do not belong in Alginomonas 
as here defined. 

The type species is Alginomonas nonjermentans K&ss et al. 

Key to the species of genus Alginomonas. 

I. Gelatin is liquefied. 

A. Grow on potato. 

1. Gray to grayish brown growth on potato. 

1. Alginomonas nonjermentans. 

2. Pinkish or ivory-colored growth on potato. 

a. Pink growth on potato. 

2. Alginomonas terrestralginica. 
aa. Ivory-colored growth on potato. 

3. Alginomonas alginovora. 

B. No growth on potato. 

4. Alginomonas fucicola. 
II. Gelatin not liquefied in seven days. 

5. Alginomonas alginica. 

1. Alginomonas nonfermentans K&ss Potato: Abundant, grayish brown 

et al., 1945. (K&ss, Lid and Molland, Norske growth. 

Videnskaps-Akad., Oslo, 1 Mat. -Naturv. Indole not produced. 

Klasse, No. 11, 1945, 9.) Hydrogen sulfide is produced. 

non.fer.men'tans. L. prefix non- not, Alginic acid is decomposed without the 

non-; L. y. fermento to ferment; M.L. part. production of acid or gas. 

adj. nonjermentans non-fermenting. Carbohydrates are not utilized. 

Small, coccoid rods. Motile with one to (.^^^.j^ ^^j^ ^^^^^^ ^e used as a sole source 

four polar fiagella. Gram-negative. , oarbon 

Good growth on ordinary media. ^t-, .. i i j- -^ j. 

^ . ^. -r ■ r ^- Nitrites produced from nitrates. 
Gelatin: Liquefaction. 

Agar colonies: Smooth, fluorescent. Aerobic. 

Broth: Turbid; sediment; no pellicle. Grows at 37° C. 

Litmus milk: Coagulated; peptonized; Chemical tolerance: No growth at pH 
reduced. 9.6. 



♦Prepared by Prof. Th. Thj0tta, Microbiological Institute, University of Oslo, Oslo, 
Norway, January, 1955. 



FAMILY IV. PSEUDOMONADACEAE 



203 



No growth in 6 per cent sodium chloride 
broth. 

Source: Five strains were isolated from 
soil. 

Habitat: Presumably soil. 

2. Alginomonas terrestralginica 

(Waksman et al., 1934) K^ss et al., 1945. 
{Bacterium terrestralginicum Waksman, 
Carey and Allen, Jour. Bact., 28, 1934, 217; 
Kiss, Lid and MoUand, Norske Viden- 
skaps-Akad., Oslo, 1 Mat.-Naturv. Klasse, 
No. 11, 1945, 9.) 

ter.res.tral.gi'ni.ca. L. noun terrestris 
land, earth; M.L. adj. alginicus pertaining 
to alginic acid from seaweed; M.L. adj. 
terrestralginicus land-alginic; presumably 
intended to mean an alginic bacterium from 
the soil. 

Long rods, 1.0 to 1.5 by 1.5 to 2.5 microns, 
with somewhat rounded ends, usually oc- 
curring singly but also in pairs, occasionally 
in chains of shorter rods. Motile. Granular. 
Gram-negative. 

Alginic acid plate: Colonies small, whitish 
in appearance with a slight metallic sheen. 

Alginic acid liquid medium: Medium at 
first clouded. Later a pellicle is formed on 
the surface of the medium; it is soon broken 
up due to active gas formation. Reaction of 
medium becomes slightly alkaline. 

Gelatin medium: Slow growth throughout 
stab, slow liquefaction at surface of medium 
at 18° C. 

Agar liquefaction: None. 

Glucose broth: Abundant turbidity; some 
sediment; no pellicle; slightly fluorescent. 

Litmus milk: Acid; milk coagulated; 
only limited digestion of coagulum. 

Potato: Abundant, pinkish, compact, 
dry growth on surface of plug, the rest of 
the plug becoming gray with a tendency to 
darkening. 

Starch plate: Limited growth along 
streak; no diastase. 

Aerobic to facultatively anaerobic. 

Optimum temperature, 30° C. 

Source: Isolated from New Jersey soil. 

Habitat: Soil. 

3. Alginomonas alginovora (Waks- 
man et al., 1934) Kiss et al., 1945. {Bac- 
terium alginovorum Waksman, Carey and 



Allen, Jour. Bact., 28, 1934, 215; K&ss, Lid 
and Molland, Norske Videnskaps-Akad., 
Oslo, I Mat.-Naturv. Klasse, No. 11, 1945, 
9.) 

al.gi.no'vo.ra. L. fem.n. alga seaweed; 
M.L. noun acidum alginicum alginic acid 
(derived from seaweed); L. v. voro to de- 
vour; M.L. adj. alginovorus alginic acid- 
destroying. 

Rods, 0.75 to 1.2 by 1.5 to 2.0 microns, 
with rounded to almost elliptical ends, 
especially when single, occurring frequently 
in pairs and even in chains. Encapsulated. 
Actively motile. Gram-negative. 

Alginic acid plate: Colony large, white 
in appearance, with coarse, granular center, 
entire margin. Clears up turbidity caused 
by alginic acid on the plate. No odor. 

Alginic acid liquid medium: Heavy pel- 
licle formation. Active production of an 
enzyme, alginase, which brings about the 
disappearance of alginic precipitate in sea- 
water medium. 

Salt-water medium: A slimy pellicle of a 
highly tenacious nature is produced, the 
whole medium later turning to a soft jelly. 

Sea-water gelatin : Active and rapid lique- 
faction in two to six days at 18° C; highly 
turbid throughout the liquefied zone. 

Agar liquefaction: Extensive softening of 
agar, no free liquid. 

Sea-water glucose broth: Abundant, 
uniform turbidity with surface pellicle; 
some strains give heavier turbidity, and 
others heavier pellicle. 

Litmus milk containing 3.5 per cent 
salt: No apparent growth. 

Potato moistened with sea water: Moist, 
spreading, ivory-colored growth; heavy 
sediment in free liquid at the bottom. 

Starch plate: Abundant, cream-colored, 
slimy growth; extensive diastase produc- 
tion. 

Aerobic to microaerophilic. 

Optimum temperature, 20° C. 

Source: Isolated from sea water, sea- 
bottom sediments and from the surface of 
algal growth in the sea. 

Habitat: Very common in the sea. 

4. Alginomonas fucicola (Waksman et 
al., 1934) Kiss et al., 1945. {Bacterium fuci- 
cola Waksman, Carey and Allen, Jour. Bact., 



204 



ORDER I. PSEUDOMONADALES 



28, 1934, 213; K&ss, Lid and MoUand, Norske 
Videnskaps-Akad., Oslo, I Mat.-Naturv. 
Klasse, No. 11, 1945, 9.) 

fu.ci'co.la. L. mas.n./tiCMS a seaweed; M. 
L. noun Fucus a genus of brown seaweeds; 
L.v. colo to inhabit; M.L. noun fucicola the 
Fucus dweller. 

Short rods, 0.6 to 1.0 by 1.0 to 1.5 microns, 
with ends rounded to almost coccoid; 
slightly curved. Actively motile with twirl- 
ing motion. Gram-negative. 

Alginic acid plate : Colonies finely granu- 
lar, entire; at first whitish, turning brown in 
three to five days, and later almost black, 
producing a deep brown, soluble pigment. 

Alginic acid liquid medium: Limited 
growth on surface in the form of a pellicle. 
Frequently produces no growth at all. 

Sea-water gelatin: Active liquefaction; 
no growth on stab; thin, fluorescent growth 
throughout liquefied zone. 

Agar liquefaction: Positive, although lim- 
ited; only softening of agar. 

Sea-water glucose broth: Faint turbidity; 
no pellicle; no sediment. 

Litmus milk containing salt: No apparent 
growth. 

Potato moistened with sea water: No 
growth. 

Starch plate: No growth. 

Aerobic. 

Optimum temperature, 20° C. 

Source : Isolated from sea water near the 
surface of the sand bottom. 

Habitat: Rare in sea water. 

5. Alginomonas alginica (Waksman et 



al., 1934) Kiss et al., 1945. {Bacterium algini- 
cum Waksman, Carey and Allen, Jour. 
Bact., 28, 1934, 213; K&ss, Lid and Molland, 
Norske Videnskaps-Akad., Oslo, I Mat.- 
Naturv. Klasse, No. 11, 1945, 9.) 

al.gi'ni.ca. L. fem.n. alga seaweed; M.L. 
adj . alginicus pertaining to alginic acid from 
seaweed. 

Rods short to almost spherical, 0.6 to 1.0 
micron in diameter. Encapsulated. Slug- 
gishly motile. Gram-negative. 

Alginic acid plate: White, finely granu- 
lated colonies with entire margin. Does not 
clear up the turbidity in plate. Odor pro- 
duced resembles that of old potatoes. 

Alginic acid liquid medium: Thin pellicle; 
weak alginase formation. 

Sea-water gelatin: Thin growth through- 
out gelatin stab; no liquefaction in 7 days 
at 18° C. 

Agar liquefaction: None. 

Sea-water glucose broth: Uniform but 
very limited turbidity; no pellicle; no sedi- 
ment. 

Litmus milk containing salt : No apparent 
growth. 

Potato moistened with sea water: Moist, 
spreading, cream-colored growth; heavy 
sediment in free liquid at bottom. 

Starch plate: Limited, pale blue growth; 
no diastase. 

Aerobic. 

Optimum temperature, 20° C. 

Source: Isolated from sea water and from 
the surface of algal growth. 

Habitat: Common in sea water. 



Genus X. Mycoplana Gray and Thornton, 1928.* 
(Cent. f. Bakt., II Abt., 73, 1928, 82.) 

My.co.pla'na. Gr. tnyces fungus; Gr. planus a wandering; M.L. fem.n. Mycoplana fungus 
wanderer. 

Cells branching, especially in young cultures. Frequently banded when stained. Polar 
flagellate. t Capable of using phenol or similar aromatic compounds as a sole source of 
energy. Grow well on standard culture media. From soil. 

The type species is Mycoplana diniorpha Gray and Tho rnton. 

* Prepared by Prof. Robert S. Breed, Cornell University, Geneva, New York, January, 

1954. 

t The orginal statements regarding the flagellation of these species are contradictory. 
The first reads "Polar, peritrichous"; the second "Polar or peritrichous".— Editors. 



FAMILY IV. PSEUDOMONADACEAE 



205 



I. Gelatin not liquefied 
II. Gelatin liquefied. 



Key to the species of genus Mycoplana. 

1. Mycoplana dimorpha. 

2. Mycoplana bullata. 



1. Mycoplana dimorpha Gray and 
Thornton, 1928. (Cent. f. Bakt., II. Abt., 
73, 1928,82.) 

di.mor'pha. Gr. adj. diniurphus two forms. 

Short, curved and irregular rods, 0.5 to 
0.7 by 1.25 to 4.5 microns, showing branch- 
ing especially in young cultures. Originally 
reported as "polar, peritrichous". Draw- 
ings show some cells with a polar flagellum 
and others where the several flagella shown 
could represent a tuft of polar flagella. 
Cultures preserved in the American Type 
Culture Collection have been retested (T. 
H. Lord, Manhattan, Kansas; F. E. Clark, 
Beltsville, Maryland) and show typical 
pseudomonad cells, i.e., straight rods with a 
single polar flagellum. Meanwhile P. H. H. 
Gray (Macdonald College, Quebec) reports 
that his cultures still show branching cells 
on the media he uses. Gram-negative. 

Gelatin colonies: Circular, bufi", smooth, 
resinous, entire. 

Gelatin stab: No liquefaction. Growth 
filiform. 

Agar colonies: Circular, buff, convex, 
smooth, glistening, entire. 

Agar slant: Filiform, white, convex, 
glistening, entire. 

Broth: Turbid, with surface ring. 

Nitrites not produced from nitrates, but 
gas evolved in fermentation tubes. 

Starch hydrolyzed. 

No acid from carbohydrate media. 

Attacks phenol. 

Aerobic. 

Optimum temperature, below 30° C. 

Source : Only one strain was found in soil 
by Gray and Thornton {loc. cit.). Wood 
(Aust. Jour. Marine and Freshwater Res., 
4, 1953, 184) identifies 1010 cultures out of 
2969 cultures isolated from Australian 
marine habitats as belonging to this species. 
Some appeared on svibmerged glass slides as 
attached forms. A diversity of characters 
was found in these cultures, indicating that 
many of them should not have been identi- 



fied as belonging to this species or even to 
this genus. For example, while it is stated in 
one place that carbohydrate fermentation 
is feeble, it is stated in another place that 
about 50 per cent of the cultures actively 
fermented maltose and sucrose, these sugars 
being fermented more actively than glucose. 
Some cultures are reported as attacking 
cellulose, others as attacking alginates or 
even chitin. In other words many of the cul- 
tures identified as Mycoplana dimorpha 
possessed characters not ascribed to the 
species by Gray and Thornton. Apparently 
all cultures from marine habitats that were 
Gram-negative branching forms were identi- 
fied as Mycoplana dimorpha unless they 
showed a yellow, pink or lemon-yellow chro- 
mogenesis. Wood's work would indicate that 
branching, polar flagellate species of very 
diverse physiologies exist in marine habitats 
that are as yet scarcely studied from the 
standpoint of the species present. M. E. 
Norris of the Pacific Fisheries Experiment 
Station, Vancouver, B.C. reports (personal 
communication. May, 1954) that she also 
finds Gram-negative, branching, polar 
flagellate organisms in sea water. 

Habitat: Probably widely distributed in 
soil. Possibl}^ also found in marine habitats. 

2. Mycoplana bullata Gray and Thorn- 
ton, 1928. (Cent. f. Bakt., II Abt., 73, 1928, 
83.) 

bul.la'ta. L. adj. bullatvs with a knob. 

Rods curved or irregular in shape, branch- 
ing, 0.8 to 1.0 by 2.25 to 4.5 microns. Origi- 
nally stated to be either "polar or peri- 
trichous" in its flagellation, but recent 
studies show that the American Type Cul- 
ture Collection culture of this organism is 
polar flagellate. It resembles Mycoplana 
liiinurpha in this respect. Gram-negative. 

Gelatin colonies: Circular, buff, smooth, 
glistening; edge diffuse. Gelatin partially 
liquefied. 



206 



ORDER I. PSEUDOMONADALES 



Gelatin stab: Saccate liquefaction. 

Agar colonies: Circular, white, convex, 
smooth, glistening, entire. 

Agar slant: Filiform, white, convex, 
smooth, glistening, entire. 

Broth: Turbid. 

Nitrites not produced from nitrates. Gas, 
presumably N2, in fermentation tubes. 

Starch not hydrolyzed. 

No acid from carbohydrate media. 

Attacks phenol. 



Aerobic. 

Optimum temperature, below 30°C. 
Source: Two strains isolated from soil. 
Habitat: Probably widely distributed in 
soil. Possibly also found in marine habitats. 

Note: Species incertae sedis. Other bac- 
teria from sea water, fresh water and soil 
have been described as belonging in this 
genus. Their relationships to the species 
described by Gray and Thornton (Cent, 
f. Bakt., II Abt., 73, 1928, 82) have not yet 
been definitely established. 



Genus XI. Zoogloea Cohn, 1854.* 
(Nov. Act. Acad. Caes. Leop. -Carol. Nat. Cur., 24, 1854, 123.) 

Zo.o.gloe'a. Gr. adj. zous living; Gr. gloea glue; M.L. fem.n. Zoogloea living glue. 

Rod-shaped cells embedded in a gelatinous matrix. Free-floating forms found in fresh 
water that contains organic matter. Occur as compact masses or as branched forms. Cells 
may become detached and motile in which case they are monotrichous. 

The original description of this genus follows : 

Zoogloea. Cellulae minimae bacilliformes hyalinae, gelatina hyalina in massas globosas, 
uvaeformes, mox membranaceae consociatae, dein singulae elapsae, per aquam vacillantes. 

This may be freely translated as follows : 

Zoogloea. Transparent, very small, rod-shaped cells embedded in transparent, gelatinous, 
clustered, spherical masses. Afterwards become detached as individuals swimming to and 
fro in the water. 

Zoogloea termo Cohn, 1854, the tj^pe species (monotypy) of this genus, is generally thought 
to be unrecognizable. While awaiting further study of this problem by modern methods, it 
is recommended that Zoogloea ramigera Itzigsohn be accepted as the type species of Zoogloea 
Cohn. 



1. Zoogloea ramigera Itzigsohn, 1867, 
emend. Bloch, 1918. (Itzigsohn, Sitzungsber. 
d. Gesellschaft naturf. Freunde, Berlin, 
Nov. 19, 1867, 30; Bloch, Cent. f. Bakt., II 
Abt., 48, 1918, 44-62.) 

ra.mi'ge.ra. L. ramus a branch; L. v. gero 
to bear; M.L. adj . ramigerus branch-bearing. 

Description taken from Bloch (loc. cit.), 
who made the first cultural studies of this 
species, Butterfield (Public Health Reports, 
50, 1935, 671) and Wattie (Pub. Health Re- 
ports, 57, 1942, 1519). 

Rods, 1 by 2 to 4 microns, with rounded 
ends. Numerous cells are found embedded 
in a gelatinous, branching matrix (see Koch, 
Beitrage z. Biol. d. Pflanzen, 2, Heft 8, 1877, 
399, Taf. XIV, and Butterfield, op. cit., 
1935, plates I-IV). Free cells are motile with 



a single, long, polar flagellum. Gram-nega- 
tive. 

Bloch reports no growth at 25° C. on gela- 
tin, poor growth on nutrient agar, good 
growth in nutrient broth, weak growth in 
peptone water, very good growth in hay in- 
fusions, good growth in yeast extract water, 
no growth in liquid manure, no growth in 
beer wort, no growth on potato and no 
growth on yellow sugar beet. Butterfield re- 
ports that growth is best in aerated liquid 
media. 

Nitrites not produced from nitrates. 

Ammonia produced from peptones. 

Indole not produced. 

Hydrogen sulfide not produced. 

Methyl red negative; acetylmethylcar- 
binol not produced. 



* Revised by Mrs. James B. Lackey n^e Elsie Wattie, University of Florida, Gaines- 
ville, Florida, March, 1954. 



FAMILY IV. PSEUDOMONADACEAE 



207 



Bloch reports that sugars are utilized in 
developing cell substances. Wattie finds that 
there is evidence of slight acid production 
from glucose, lactose, xylose and mannitol, 
whereas Butterfield finds no action on all 
sugars tested. In addition to the sugars 
named above, these included sucrose, 
arabinose, galactose, mannose, cellobiose, 
raffinose, melizitose, dextrin and salicin. 

Ptire-culture "activated sludges" formed 
bj' this species have been shown to produce 
a high rate of oxidation of the pollutional 
material in sewage (synthetic and natural), 
oxidizing about 50 per cent of the 5-day bio- 
chemical oxygen demand in a 5-hour aera- 
tion period and about 80 per cent in a 24- 
hour interval. Nitrogenous materials are not 
included in this oxidation as this species is 
not capable of such action. 

Temperature relations: Optimum, be- 
tween 28° and 30° C. Good growth at 20° and 
at 37° C. Minimum, 4° C. 

Optimum pH, 7.0 to 7.4. 

Strict aerobe. 

Distinctive characters: Oxidizes sewage 
and other organic solutions. Also see 
McKinney and Horwood (Sewage and Ind. 
Wastes, 2^, 1953, 117), who found other floc- 
forming organisms besides Zoogloea ramigera 
in activated sludge; these were identified 
as Bacillus cereus, Escherichia intermedia, 
Paracolohactrum aerogenoides and Nocardia 
actinomorpha. A species of Flavobacterium 
was also found in the floes in association 
with these species. 

Source: Originally (1867) found in a cul- 
ture of decomposing algae. It has been re- 
peatedly found in materials containing de- 
composing plant materials and sewage and 
is especially common in the floes formed in 
the activated sludge process of purifying 
sewage. 

Habitat: Produces zoogloeal masses in 
water containing decomposing organic mat- 
ter. Common. 

2. Zoogloea filipendula Beger, 1928. 



(Kl. Mitt. d. Ver. f. Wasser-, Boden- und 
Lufthyg., Berlin-Dahlem, 4, 1928, 143; also 
see Beger, Zent. f. Bakt., I Abt., Orig., 154, 
1949, 61.) 

fi.li.pen'du.la. L. nounfilum a thread; L. 
adj. penduhis hanging down; M.L. adj. 
filipendulus thread hanging down. 

Description prepared by Prof. H. Beger, 
Berlin-Dahlem, Germany. 

Cells coccoid (0.8 micron in diameter) to 
rod-shaped (0.8 by 2.0 microns). The cells 
are surrounded by a gelatinous mass which 
varies in size from 1.5 to 2.0 by 4.5 cm and 
which is composed of numerous, more or 
less spherical masses 3 to 5 mm long. The 
largest cells completely fill the newly formed 
globules which lie at the end of filaments 
hanging downward from zoogloeal masses 
suspended from the under surface of pump 
pistons and other submerged objects; the 
cells in the older globules are smaller (0.4 
by 0.7 micron) and are found near the sur- 
face of the globule, the interior being rela- 
tively free of cells. 

Several other bacteria are found in asso- 
ciation with this species. As a result, the 
gelatinous mass appears rust-colored (cov- 
ered with iron bacteria) when found in acid 
waters and grayish white when isolated from 
water that is neutral. 

Nutrient gelatin: Only the small forms, 
such as those found in older globules, are 
able to grow on this medium. Substantial 
growth occurs at the bottom of the stab in 
48 hours. 

Source: Isolated from pump pistons and 
other submerged objects from a waterworks 
near Berlin. 

f Habitat: Found in water contaminated 
with sewage or industrial wastes. 

Note: Species incertae sedis: For species 
that resemble those placed in the genus 
Zoogloea Cohn in many important respects, 
see Nevskia ramosa Famintzin and Myco- 
nostoc gregarium Cohn. Additional species 
have also been placed in the genus Zoogloea. 



Genus XII. Halobacterium Elazari-Volcani, 1940.* 

(Elazari-Volcani, Studies on the Microflora of the Dead Sea. Thesis, Hebrew Univ., Jeru- 
salem, 1940, V and 59; not Halibacterium Fischer, Ergebnis.se der Plankton-E.xpedition der 

* Prepared by Dr. B. Elazari-Volcani, The Weizmann Institute of Science, Rehovoth, 
Israel, February, 1955. 



208 



ORDER I. PSEUDOMONADALES 



Humboldt-Stiftung, 1894, 19; not Halophilus Sturges and Heideman (nomen nudum), Abst. 
of Bact., 8, 1924, 14; not Halobacterium Schoop (nomen nudum), Zent. f. Bakt., I Abt., Orig., 
134., 1935, 26; Halobacter Anderson, Applied Microbiol., 2, 1954, 66.) 

Ha.lo.bac.te'ri.um. Gr. noun hals salt; Gr. dim. noun bacterium a small rod; M.L. neut.n. 
Halobacterium the salt bacterium. 

Obligate halophilic, rod-shaped bacteria which are highly pleomorphic. Require at least 
12 per cent salt for growth, and will live even in saturated brine solutions. Motile species 
are polar flagellate; some species are non-motile. Gram-negative. Usually chromogenic, 
producing non-water-soluble, carotenoid pigments which vary in shade from colorless 
to orange or even brilliant red. Carbohydrates may or may not be attacked without the 
production of visible gas. Nitrates are reduced, occasionally with the production of gas. 
Found in tidal pools, especially in the tropics, salt ponds, salt seas or other places where 
heavy brines occur naturally; also found on salted fish, salted hides and similar materials. 

The type species is Halobacterium salinarium Elazari-Volcani. 



Key to the species of genus Halobacterium. 



I. Gas not produced from nitrates. 

A. Nitrites not produced from nitrates. 

1. Pale pink to scarlet chromogenesi 

2. Pink to dark red chromogenesis. 

B. Nitrites produced from nitrates. 

II. Gas produced from nitrates. 

A. Produces acid from glucose. 

B. Does not produce acid from glucose. 



1. Halobacterium salinarium. 



2. Halobacterium cutirubrum. 



3. Halobacterium halobium. 



4. Halobacterium marismortui. 



5. Halobacterium trapanicum. 



1. Halobacterium salinarium (Harrison 
and Kennedy, 1922) Elazari-Volcani, 1940. 
{Pseudomonas salinaria Harrison and Ken- 
nedy, Trans. Royal Soc. of Canada, 16, 
1922, 121; Flavobacterium (Halobacterium) 
salinarium Elazari-Volcani, Studies on 
the Microflora of the Dead Sea. Thesis, 
Hebrew Univ., Jerusalem, 1940, 59.) 

sa.li.na'ri.um. L. adj. salinarius of salt 
works. 

Occurs as spheres and rods. The spheres 
are 0.8 to 1.4 microns in diameter. The rods, 
0.6 to 1.5 by 1.0 to 6.0 microns, occur singly 
as ovoid, amoeboid, clavate, cuneate, trun- 
cate, spindle- and club-shaped, pyriform 
and other irregular forms. Age of culture 
and nature of medium influence the size and 
shape of cells. Reproduction is by means of 
fission but apparently also by budding. 
Motile by means of a polar flagellum at one 
or both poles. Gram-negative. 

Does not grow on ordinary culture media 



unless supplemented with 16 to 35 per cent 
sodium chloride and 2 per cent MgS04-7H20 
(Katznelson and Lochhead, Jour. Bact., 
64, 1952, 97) . Grows well on salted fish and 
hides. 

Gelatin (salt) : Slow liquefaction (Katz- 
nelson and Lochhead, loc. cit.). 

Codfish agar colonies (16 to 30 per cent 
salt) : In seven days punctiform, smooth, 
raised, entire, granular, pale pink to scarlet 
(Ridgway chart), 1.5 mm in diameter. 

Milk salt agar (24 to 35 per cent salt) : 
Pink colonies 4 to 5 mm in diameter, be- 
coming scarlet. 

Putrefactive odor. Definite proteolytic 
zones develop (Lochhead, Can. Jour. Res., 
10, 1934, 275). 

Codfish agar slant (16 to 35 per cent salt) : 
In seven days moderate, filiform, slightly 
raised, glistening, smooth, translucent, 
bright red, viscid. Unpleasant odor. 

Milk salt agar slants (24 to 35 per cent 



FAMILY IV. PSEUDOMONADACEAE 



209 



salt): Filiform, slightly raised, smooth, 
glistening, butyrous, bright red (Lochhead, 
loc. cit). 

Broth (5 to 35 per cent salt) : No growth. 
Good growth when grown according to di- 
rections of Katznelson and Lochhead {op. 
cit., 1952,97). 

Codfish broth (25 per cent salt): Turbid, 
dense, pink sediment; imperfect, pink pel- 
licle. 

Potato immersed in brine: No growth. 

Indole not produced. 

Hj'drogen sulfide is produced. 

No indication of action on carbohydrates. 

Starch not hydrolyzed. 

Cannot utilize inorganic nitrogen as a sole 
source of nitrogen. Tests (Warburg respir- 
ometer) show active oxidation of amino 
acids (such as serine, glutamic acid and as- 
partic acid); also active oxidation of glj'c- 
erol. 

Nitrites not produced from nitrates 
(Lochhead, op. cit., 1934, 275). 

Aerobic. 

Optimum temperature, 37° C. Grows at 
22° C. 

Optimum salinity, 28 to 32 per cent (Loch- 
head, loc. cit.). When the salt concentration 
is reduced to 8 per cent, cells are ruptured. 

Distinctive characters: See Halobacterium 
cutirubrum. 

Source: Isolated from cured codfish 
(Harrison and Kennedy, op. cit., 1922, 121) 
and salted fish (Browne, Absts. Bact., 6, 
1922, 25, and Proc. Soc. Exp. Biol, and Med., 
19, 1922, 321) ; also from salted hides (Loch- 
head, op. cit., 1934, 275). 

Habitat: Produces a reddening of salted 
fish and hides where untreated solar salt is 
used. Abundant in tidal pools along shores 
of tropical seas. Reddens the water in the 
pools where solar salt is produced as soon as 
the brine is concentrated to 18 per cent salt. 
Common on untreated solar salt. 

2. Halobacterium cutirubrum (Loch- 
head, 1934) Elazari-Volcani, 1940. {Serratia 
cutirubra Lochhead, Can. Jour. Research, 
10, 1934, 275; Flavobacterium {Halobacterium) 
cutirubrum Elazari-Volcani, Studies on the 
Microflora of the Dead Sea. Thesis, Hebrew 
Univ., Jerusalem, 1940, 59.) 



cu.ti.ru'brum. L. nonn cutis the skin; L. 
adj . ruber red; M.L. adj . cutirubrus skin-red. 

Occurs as spheres and rods. The spheres 
are 1.0 to 2.0 microns in diameter, and the 
rods measure 0.7 to 4.0 by 1.5 to 8.0 microns. 
Age of culture and nature of medium influ- 
ence the size and shape of cells. Rod forms 
are motile with a single polar flagellum; 
coccoid forms are motile when young. Gram- 
negative. 

No growth on ordinary media. 

Milk agar (20 per cent salt to saturation; 
optimum 28 to 32 per cent) colonies : 3 to 4 
mm in diameter, round and slightly convex, 
pink to dark red (rose dorde, Ridgway 
chart) . 

Milk agar slants: Growth filiform, slightly 
spreading, rather flat with smooth, glisten- 
ing surface and membranous consistency. 
Proteolytic action. 

Liquid media: No or slight growth. Good 
growth when grown according to directions 
of Katznelson and Lochhead (Jour. Bact., 
64, 1952, 97). 

Gelatin (salt): Pronounced liquefaction. 

Indole not produced (Lochhead, op cit., 
1934, 275) ; faint positive (Gibbons, Jour. 
Biol. Board Canada, 3, 1936, 75). 

Hydrogen sulfide is produced. 

Tests (Warburg respirometer) show slow 
oxidation of amino acids (such as serine, 
glutamic acid and aspartic acid) ; also slow 
oxidation of glycerol. 

Nitrites not produced from nitrates. 

Diastatic action negative. 

No carbohydrate fermentation. 

Aerobic. 

Optimum temperature, 37°C. 

Salt tolerance: Halophilic, obligate. No 
rupturing of cells occurs when the salt con- 
centration is reduced to 8 per cent; rup- 
turing occurs when the salt concentration is 
4 per cent. 

Distinctive characters: Resembles Halo- 
bacterium salinarium. Differs from it in mor- 
phology and cultural characters, particu- 
larly as regards color and consistency. More 
actively proteolytic. Slower oxidative ac- 
tion on amino acids and glycerol. Ruptur- 
ing of cells does not occur as rapidly when 
the salt concentration is reduced. 



210 



ORDER I. PSEUDOMONADALES 



Source: Isolated from salted hides which 
were presumably salted with solar salt. 
Habitat: Sea water and solar salt. 

3. Halobacterium halobium (Petter, 
1931) Elazari-Volcaui, 1940. (Microbe du 
rouge de morue, Le Dantec, Ann. Inst. 
Past., 5, 1891, 656; also see Le Dantec, 
Compt. rend. Soc. Biol., Paris, 61, 1906, 136; 
Bacillus halobius ruber Klebahn, Mitteil. 
a. d. Inst. f. allg. Bot. i. Hamburg, 4, 1919, 
47; abst. in Cent. f. Bakt., II Abt., 52, 1921, 
123; Bacterium halobium Petter, Proc. Kon. 
Acad. V. Wetensch. Amsterdam, 34, 1931, 
1417; also see Petter, Over roode en andere 
bacterien van gezouten visch. Thesis, 
Utrecht, 1932; Flavobacterium {Halobac- 
terium) halobium Elazari-Volcani, Studies on 
the Microflora of the Dead Sea. Thesis, 
Hebrew Univ., Jerusalem, 1940, V and 59.) 

ha.lo'bi.um. Gr. noun hals salt; Gr. noun 
bius life; M.L. adj. halobius living on salt. 

Rods, the length of which varies greatly 
with the medium and age of culture: 0.6 to 
0.9 by 2.0 to 6.0 microns in young cultures 
grown on agar (30 per cent NaCl + 1 per 
cent peptone "Poulenc"); 2.0 to 27.0 mi- 
crons long in liquid peptone media, occur- 
ring singly. (Klebahn described rods up to 
45 microns in liquid media; in old cultures 
(horse-serum agar), irregular involution 
forms appear which are round, ovoid or 
coccus-like, 1.0 to 1.5 by 1.7 to 2.7 microns.) 
Cells from opaque colonies contain charac- 
teristic gas vacuoles. The cells are very sen- 
sitive to changes in salt concentration; be- 
low 12 per cent NaCl and in w^ater, they 
swell and form ovoid, amoeboid and club-, 
spindle-, drumstick- and pear-shaped arte- 
facts. Because of these irregular forms, the 
organism was described by several investi- 
gators as polymorphic (Cloake, Dept. of 
Scientific and Ind. Research, Food Investi- 
gation Board No. 18, London, 1923). Slightly 
motile with a pendulum-like movement; 
flagella observed with electron microscope 
(Houwink, Jour. Gen. Microlnol., 15, 1956, 
146). Gram-negative. 

Agar colonies (30 per cent NaCl -f 1 per 
cent peptone "Poulenc"): Circular, trans- 
parent or opaque; color varies from almost 
white to orange, red, violet and purple; the 
color of the colonj^ also changes during the 
course of growth. 



Broth (30 per cent NaCl + 1 per cent pep- 
tone "Poulenc"): Pellicle; turbid; colored 
sediment. 

Asparagine broth (30 per cent NaCl -|- 3 
per cent asparagine) : No growth. 

Indole not produced. 

No acid from glucose, sucrose or maltose 
(tests made in 30 per cent salt + 1 per cent 
peptone -|- 2 per cent carbohydrate). 

Nitrites produced from nitrates; no gas is 
produced. 

Catalase-positive. 

Aerobic. 

Optimum temperature, 37° C. 

Salt tolerance: Halophilic, obligate; 
grows above 12 per cent NaCl up to satura- 
tion. 

Distinctive character: The pigment is 
soluble in methanol, ethanol, acetone, 
chloroform, carbon disulfide, benzol, petro- 
leum ether, toluene and xylene. The carot- 
enoids are named bacterio-ruberine a and /3. 

Source: Seven different strains were iso- 
lated from reddened, salted codfish and her- 
ring. 

Habitat: Produces a red discoloration on 
salted herring and codfish. 

4. Halobacterium marismortui Ela- 
zari-Volcani, 1940. (Flavobacterium {Halo- 
bacterium) maris-mortui (sic) Elazari-Vol- 
cani, Studies on the Microflora of the Dead 
Sea. Thesis, Hebrew Univ., Jerusalem, 1940, 
V and 48.) 

ma.ris.mor'tu.i. L. noun mare the sea; 
L. gen. noun maris of the sea; L. adj. mortuus 
dead; M.L. gen. noun marismortui of the 
Dead Sea. 

Rods, the length and shape varj'ing 
greatly with the medium : in Dead Sea water 
-f 1 per cent proteose peptone, the cells 
occur singly and measure 0.5 by 1.6 to 3.0 
microns; in 24 per cent salt + 1 per cent 
peptone and on agar + peptone + salt and 
on Dead Sea water + peptone + agar, the 
cells are spheroids which measure 1.0 to 
1.5 microns in diameter. Non-motile. When 
stained, the rods burst while the spheroids 
retain their shape. Gram-negative. 

Gelatin stab (18 per cent salt + 1 per cent 
peptone + 30 per cent gelatin) : Surface 
growth. No liquefaction (2 months). 

Agar colonies (24 per cent salt + 1 per 



FAMILY IV. PSBUDOMONADACEAE 



211 



cent proteose peptoue + 2 per cent KNO3) : 
Circular, smooth, entire, raised to convex, 
butyrous, glistening, opaque with a slightly 
transparent margin which is less colored, 
orange-brown, orange-red or orange-yellow. 

Agar slant (24 per cent salt + 1 per cent 
peptone + 2 per cent KNO3): Growth 
moderate, filiform, raised to convex, glisten- 
ing, smooth, butyrous, opaque, orange-red. 

Broth (24 per cent salt + 1 per cent pep- 
tone) : Turbid; orange-red pellicle; slightly 
viscous sediment. 

Asparagine broth (24 per cent salt + 1 
per cent asparagine): Turbid. 

Indole not produced. 

Acid from glucose, fructose, mannose and 
glycerol ; slight acid from xylose and salicin 
(tests made in 24 per cent salt + 1 per cent 
peptone + 1 per cent carbohydrate during 
3 weeks). 

Starch not hj-drolyzed. 

Nitrites rapidly produced from nitrates; 
gas is produced (tests made in 24 per cent 
salt + 1 per cent peptone + 2 per cent 
KNO3). 

Aerobic. 

Optimum temperature, 30° C. 

Salt tolerance: Halophilic, obligate; 
grows in 18 per cent to saturated salt solu- 
tions; slight growth in 15 per cent salt. 

Distinctive character: The pigment pro- 
duces a blue color with concentrated sul- 
furic acid, thus suggesting a carotenoid; it 
is very soluble in pyridine, less soluble in 
methanol, ethanol and chloroform, slightly 
soluble in acetone, very slightly so in ben- 
zol and insoluble in xylene and petroleum 
ether. 

Source: Isolated from Dead Sea water. 

Habitat: Salt lakes. 

5. Halobacteriuin trapanicum (Petter, 
1931) Elazari-Volcani, 1940. (Bacterium 
trapanicum Petter, Proc. Kon. Acad. v. 
Wetensch. Amsterdam, S4, 1931, 1417; also 
see Petter, Over roode en andere bacterien 
van gezouten visch. Thesis, Utrecht, 1932; 
Flavohacterium (Halobacterium) trapanicum 
Elazari-Volcani, Studies on the Microflora 
of the Dead Sea. Thesis, Hebrew Univ., 
Jerusalem, 1940, V and 59.) 

tra.pa'ni.cum. M.L. adj. trapanicus per- 
taining to "Trapani" salt. 



Rods, 0.6 by 1.5 to 3.5 microns. The length 
and shape of the cells may vary greatly with 
the medium: in Dead Sea water + 1 per cent 
proteose peptone, the cells occur singly and 
are 0.45 to 0.55 by 1.5 to 4.8 microns with 
occasional rods measuring 8.0 to 16.0 mi- 
crons in length; in 24 per cent salt + 1 per 
cent peptone, the short rods predominate; 
in 24 per cent salt + 1 per cent peptone + 2 
per cent KNO3 agar, the cells are ovoid, 
measuring 1.0 to 1.5 microns in diameter. 
Non-motile. Gram-negative. 

Gelatin stab (18 per cent salt -f 1 per 
cent peptone -1- 30 per cent gelatin) : Surface 
growth. No liquefaction (2 months). 

Agar colonies (24 per cent salt + 1 per 
cent proteose peptone + 2 per cent KNO3) : 
Small (1 to 2 mm in diameter), circular, 
smooth, entire, convex, glistening, trans- 
parent, light orange or slightly colorless. 

Agar slant (24 per cent salt -f 1 per cent 
peptone + 2 per cent KNO3): Growth 
moderate, filiform, raised, glistening, 
smooth, opaque or slightly transparent, 
light orange. 

Broth (Dead Sea water -f 1 per cent pep- 
tone) : Orange-rose pellicle; turbid; orange 
sediment. In 24 per cent salt + 1 per cent 
peptone: orange -rose ring; turbid; orange 
sediment. 

Asparagine broth (24 per cent salt + 1 
per cent asparagine) : Moderately turbid. 

Indole not produced. 

No acid from arabinose, xylose, glucose, 
fructose, galactose, mannose, lactose, su- 
crose, maltose, raffinose, inulin, dextrin, 
glycerol, mannitol or salicin (tests made in 
24 per cent salt + 1 per cent peptone + 1 
per cent carbohydrate during 3 weeks). 

Starch not hydrolyzed. 

Nitrites rapidly produced from nitrates; 
gas is produced (tests made in 24 per cent 
salt + 1 per cent peptone + 2 per cent 
KNO3). 

Catalase-positive. 

Aerobic. 

Optimum temperature, between 30° and 
37° C. 

Salt tolerance: Halophilic, obligate; 
grows in 18 per cent to saturated salt solu- 
tions ; slight growth in 15 per cent salt. 

Distinctive character: The pigment pro- 



212 ORDER I. PSEUDOMONADALES 

duces a blue color with concentrated sul- Source: Isolated from "Trapani" salt 

furic acid, thus suggesting a carotenoid. r..^^ • -d ,~.j , , 

,. 1 ui ■ -J- 1 , , , • "^"^ ^ cannery in Bergen (Norway) and 

Very soluble in pyridine; less soluble in = \ j / 



methanol, ethanol and chloroform; slightly 



from the water of the Dead Sea. 



soluble in acetone, very slightly so in ben- Habitat: Sea salt, sea-water brine and 

zol; insoluble in xylene and petroleum ether. salt lakes. 



FAMILY V. CAULOBACTERACEAE HENRICI AND 
JOHNSON, 1935, EMEND. BREED.* 

(Includes the typical families and genera of Caulobacteriales (sic) Henrici and Johnson, 
Jour. Bact., 29, 1935, 4 and ibid., 30, 1935, 83. The Order Caulobacterales Henrici and Johnson 
was redefined as a Sub-order, Caidobacteriineae (sic), by Breed, Murray and Kitchens, Bact. 
Rev., 8, 1944, 255. The present emendation reduces the Order Caulobacterales, as originally 
defined, to the status of a family in the Sub -order Pseudomonadineae Breed, Murray and 
Smith.) 

Cau.lo.bac.ter.a'ce.ae. M.L. neut.n. Caulobacter the type genus of the family; -aceae 
ending to denote a family; M.L. fem.pl.n. Caulobacteraceae the Caulobacter famil}^ 

Non-filamentous, rod-shaped bacteria normally attached by branching or unbranching 
stalks to a substrate. In one floating form the stalks are branched. Cells occur singly, in 
pairs or in short chains. The cells are asymmetrical in that a stalk is developed at one end 
of the cell or ferric hydro.xide or other material is secreted from one side of the cell to form 
stalks. Cells are polar flagellate in the free-living state, non-motile in the attached forms. 
Gram-negative. Multiply by transverse fission, the daughter cells remaining in place or 
swimming away as swarm cells. Typically fresh- or salt-water forms. 

The family Caulobacteraceae, as here defined, includes the genera Caulobacter Henrici and 
Johnson, Gallionella Ehrenberg, Siderophacus Beger and Nevskia Famintzin. 

The species in this family as presented here have close affinities with the species in the 
family Pseudomonadaceae . In all cases where motility has been observed and stains made, 
polar flagella have been found. It seems probable that when the life histories of these seden- 
tary bacteria have been investigated, it will be found that practically all, if not all, of these 
attached forms develop a motile stage. Such a stage permits the distribution of the species 
in its environment. 

The stalked bacteria studied by Henrici and Johnson (op. cit., 30, 1935, 83) were of fresh- 
water origin. Bacteria of this type are found, however, equally if not more abundantly in 
marine habitats where they play their part in the fouling of underwater surfaces. ZoBell 
and Upham (Bull. Scripps Inst, of Oceanography, LaJolla, California, 5, 1944, 253) summa- 
rize this situation as follows: "Many of the bacteria found in sea water are sessile or peri- 
phytic, growing preferential!}^ or exclusivelj^ attached to solid surfaces. The sessile habit 
of marine bacteria is most pronounced when they are growing in very dilute nutrient solu- 
tions, such as sea water, to which nothing has been added. . . . Most sessile bacteria appear 
to attach themselves tenaciously to solid surfaces by exuding a mucilaginous holdfast. A 
few have stalks. Some of the sessile bacteria grow on the walls of the culture receptacle 
without clouding the medium itself.". 

The submerged-slide technique as employed by Henrici (Jour. Bact., 25, 1933, 277) and 

* Redefined and rearranged by Prof. Robert S. Breed, Cornell University, Geneva, New 
York, December, 1953. Prof. Herbert Beger, Institut fiir Wasser-, Boden- und Lufthygiene, 
Berlin-Dahlem, Germany, has given this section a further revision so as to include genera 
and species not previously recognized in the Manual, February, 1954. 



FAMILY V. CAULOBACTERACEAE 213 

by ZoBell and Allen (Proc. Soc. Exper. Biol, and Med., 30, 1933, 1409) has proved to be 
most useful for studying bacteria that live attached to a substrate. 

The species included in Pasteuria Metchnikoff and Blaslocmdis Henrici and Johnson 
reproduce by a curious form of fission or budding. They have been transferred to a new- 
Order, Hyphomicrobiales Douglas. 

Key to the genera of family Caulobacteraceae. 

I. Long axis of cell coincides with axis of stalk. Stalks slender. 

Genus I. Caulobacter , p. 213. 
II. Long axis of cell transverse to long axis of stalk. Stalks may be twisted and branched. 

A. Stalks are band-shaped or rounded. Contain ferric hydroxide. 

1. Stalks band-shaped and twisted. Dumb-bell-shaped in cross section. 

Genus II. Gallionella, p. 214. 

2. Stalks horn-shaped, not twisted. Round in cross section. 

Genus III. Siderophacus, p. 216. 

B. Stalks lobose, composed of gum. Forming zoogloea-like colonies. Free-floating. 

Genus IV. Nevskia, p. 216. 

Genus I. Caulobacter Henrici and Johnson, 1935. 
(Jour. Bact., 29, 1935, 4; ihid., 30, 1935, 83.) 

Cau.lo.bac'ter. L. noun caxdis a plant stem or stalk; M.L. noun bader masculine form of 
Gr. neut.n. bactrum a rod; M.L. mas.n. Caulobacter stalk rod. 

Stalked, curved, rod-shaped bacteria, the long axis of the elongated cells coinciding with 
the long axis of the stalks. Young cells motile by means of a single polar flagellum. Old cells 
attached to submerged objects by a stalk that is a continuation of the cell. A holdfast is de- 
veloped at the distal end. Multiplication of cells is by transverse binary fission. Periphytic, 
growing upon submerged surfaces. 

The type species is Caulobacter vibrioides Henrici and Johnson emend. Bowers et al. 

1. Caulobacter vibrioides Henrici and Agar colonies: Surface colonies up to 5 
Johnson, 1935, emend. Bowers et al., 1954. mm in diameter, round, smooth, slightly 
(Henrici and Johnson, Jour. Bact., 30, 1935, raised, glistening, finely granular in the 
83; Bowers, Weaver, Grula and Edwards, center, grayish white, with center and re- 
Jour. Bact., 68, 1954, 194.) verse side becoming brownish yellow. Sub- 

vib.ri.oi'des. L.v. vibro to vibrate; M.L. surface colonies dense, brownish yellow, 

noun Vibrio name of a genus; Gr. noun lenticular, up to 0.5 mm in diameter and 1.0 

eidus shape, form; M.L. adj. vibrioides re- mm in length, 

sembling a vibrio. Agar slant: Growth filiform, grayish 

Cells elongated, curved, vibrio-like, with white, glistening, viscid, 

rounded ends, 0.5 to 1.2 by 1.5 to 3.0 mi- Broth: Moderate turbidity with slightly 

crons; filamentous forms occasionally pro- viscid sediment, 

duced. Young cells actively motile with a Litmus milk: Unchanged, 

single polar flagellum; older cells develop p^^^^^^ kittle or no growth, 
a stalk at the flagellated end. The stalk has 
a central filament or tube and a membrane 
that is continuous with the cell wall. Organ- 
isms attached singly or in rosettes, with 



Indole not produced. 

Nitrites not produced from nitrates. 

No acid or gas from carbohydrates. 



stalks attached to a common holdfast. Usu- Requires riboflavin, phosphates, iron and 

ally surrounded by a slime layer. Gram- an organic source of energy for growth. Glu- 



negative. 



cose, maltose or casamino acids are used as 



Gelatin: Surface growth and filiform sources of carbon and energy; sodium bi- 
growth in stab without liquefaction. carbonate, sodium lactate, sodium acetate 



214 ORDER I. PSEUDOMONADALES 

or glycerol not utilized. Ammonium sulfate ander, Minnesota, and other fresh-water 
or casamino acids used as sources of nitro- lakes (Henrici and Johnson, op. cit., 30, 
gen; ammonium nitrate not utilized. 1935, 83). Also found in well-water in Ken- 
Optimum temperature, 30° C. tucky (Bowers et al., op. cit.). 
Aerobic, facultative. Habitat: Water, where it grows upon firm 
Source: Found frequently in Lake Alex- substrates.* 

Genus II. Gallionella Ehrenberg, 1838.-f 

(Ehrenberg, Die Infusionsthierchen, 1838, 166; not Gaillonella Bory de St. Vincent, Diet. 

Classique d'Hist. Nat., 4, 1823, 393; Didymohelix Griffith, Ann. 

Mag. Nat. Hist., Ser. 2, 12, 1853, 438.) 

Gal.li.o.nel'la. Named for Benjamin Gaillon, receiver of customs and zoologist (1782- 
1839) in Dieppe, France; M.L. dim. ending -ella; M.L. fem.n. Gallionella a generic name. 

Cells kidney-shaped or rounded. Placed at the end of the stalk with the long axis of the 
cell transverse to the long axis of the stalk. Stalks secreted by the cells are slender and 
twisted. Branch dichotomously or in the form of umbels. Stalks more or less dumb-bell or 
bisquit-shaped in cross section. Composed of ferric hydroxide, completely dissolving in 
weak acids. Two polar flagella are present when the cells are motile. Gram-negative. Multi- 
plication by fission of the cells, the daughter cells remaining at first at the end of the stalk; 
later they may be liberated as swarm cells. Grow only in iron-bearing waters. Do not store 
manganese compounds. From both fresh and salt water. When the first species was discov- 
ered the twisted stalks were thought to be a chain of diatoms. 

The type species is Gallionella ferruginea Ehrenberg. 

Key to the species of genus Gallionella. 

I. Stalks branched. 

A. Stalks dichotomously branched. 
1. Stalks slender, spirally twisted, 
a. Cells small, stalks very slender. 

1. Gallionella ferruginea. 

* The papers by Houwink (Antonie van Leeuwenhoek, 21, 1955, 29) and by Kandler, 
Zehender and Huber (Arch. f. Mikrobiol., 21, 1954, 57) were received after the manuscript 
covering the family Caulobacteraceae was prepared. They give further information regard- 
ing the structure and function of the stalk of Caulobacter sp. Clearly the stalks developed 
by species in this genus are quite different in nature from the stalks of ferric hydroxide or 
gum secreted by the cells of other species placed in other genera of this family. 

t Gallionella Ehrenberg is accepted and is continued in use in this edition of the Manual 
although under a strict interpretation of Rules of Nomenclature it should apparently be 
regarded as a homonym and therefore illegitimate. Gaillonella Bory de St. Vincent, proposed 
as the name of a genus of algae, appears to have priority (see Internat. Bull. Bact. Nomen. 
and Tax., 2, 1951, 96). However, Gaillonella B. de St. V. is no longer used by students of 
diatoms so that Gallionella E. may be retained as a gemis conservandum in bacteriology with- 
out causing confusion. Unless Gallionella E. is retained, the little used Didymohelix Griffith 
must be again introduced into the Manual with the formation of a series of new combina- 
tions. 

The situation is complicated because the final settlement of this problem of nomenclature 
requires action both by the Judicial Commission of the International Association of Micro- 
biologists and the Special Committee on Diatomaceae of the International Botanical Con- 
gress. The majority of the special students of iron bacteria have accepted and used Gallion- 
ella E., e.g. Molisch (1910), Naumann (1921), Cholodny (1924), Butkevich (1928), Dorff 
(1934), Henrici and Johnson (1934), Beger (1941) and Pringsheim (1952). 



FAMILY V. CAULOBACTERACEAE 



215 



aa. Cells longer, stalks broader. 

2. Galliunella major. 
2. Stalks short, thick, not definitely in spirals. 

3. GallioneUa minor. 
B. Stalks branching in simple or compound umbels. 

4. GallioneUa umbellata. 
II. Stalks unbranched. 

5. GallioneUa infiircata. 



1. GallioneUa ferruginea Ehrenberg, 
1836. {Gaillonella ferruginea (sic) Ehrenberg, 
Vorl. Mittheil. ii. d. wirkl. Vorkommen 
fossiler Infusionen u. ihre grosse Verbrei- 
tung, Ann. Phys., Ser. 2, 8, 1836, 217; 
GallioneUa ferruginea Ehrenberg, Die Infu- 
sion thierchen, 1838, 166; Didymohelix ferru- 
ginea Griffith, Ann. Mag. Nat. Hist., Ser. 2, 
12, 1853, 438.) 

fer.ru.gi'ne.a. L. adj. ferrugineus of the 
color of iron rust. 

Kidney-shaped cells. The full grown bac- 
teria are 0.5 to 0.6 by 1.2 to 1.5 microns. The 
cells secrete colloidal ferric hydroxide from 
the concave portion of the cell, forming 
band-like stalks 0.6 to 3.3 microns in width 
and as much as 200 microns and more in 
length. A rotatory motion of the cells gives 
rise to a spiral twisting of the stalks. 

In the older studies, the stalks were de- 
scribed as the organism, the minute cells at 
the tip having been dislodged or at least 
overlooked. The cells lie at the tip of the 
stalk and multiply by transverse binary 
fission. This gives rise to a dichotomous 
branching of the stalks. Stalks become very 
long and slender, with smooth edges. 

Not cultivated in artificial media. 

Distribution: Usually the branched stalks 
are attached separately in great numbers to 
solid surfaces. They may, however, float in 
irregular floes distributed throughout the 
water. Less commonly they form balls up 
to 3.0 microns in diameter. In these the 
stalks radiate from a center and such groups 
have been described as Gloeosphaera ferru- 
ginea Rabenhorst. In a third variety, solid 
tubercles richly encrusted with ferric com- 
pounds are formed. These are found in old 
pipelines or they may occur free in nature. 
These tubercles have been named Sphaero- 
fhrix latens Perfiliev. 

Habitat: Found in cool springs and brooks 



which carry reduced iron in solution; also 
found in wells, in storage basins in water- 
works and in pipe lines. 

2. GallioneUa major Cholodny, 1927. 
(Trav. Station, biolog. du Dniepre Acad, 
des Sci. de I'Ukraine, Classe Sci. Phys. et 
Math., 3, Livre 4, 1927.) 

ma'jor. L. comp. adj. major larger. 

Very similar to GallioneUa ferruginea, but 
the cells are distinctly larger (1.0 by 3.0 
microns). Stalks are 3.0 to 6.0 microns broad. 
Some cells that fail to divide reach a length 
of 7 microns or more; these form stalks of 
double the normal width. 

The cells contain one or more vacuoles, 
apparently filled with an iron compound. 

Source: Found in springs near Krassnodar 
(Caucasus). 

Habitat: Found in iron-bearing waters. 

3. GallioneUa minor Cholodny, 1924. 
(Ber. d. deutsch. Bot. Ges., 42, 1924, 42; also 
see Cholodny, Die Eisenbakterien, Pflan- 
zenforschung. Heft 4, 1926, 47.) 

mi 'nor. L. comp. adj. minor smaller. 

Cells as in GallioneUa ferruginea, but 
stalks are shorter, thicker and more band- 
like than twisted. After division, cells do not 
separate as quickly as in GallioneUa ferrii- 
ginea. The branches gradually become en- 
crusted until the stalks are quite obscured. 
Branches of stalks are not more than 20 to 
30 microns long. 

Source : Found in a small spring near the 
Biological Station in Dniepre. Also found 
by Beger (Ber. d. deutsch. Bot. Ges., 62, 
1944, 11) in material from Camerun in 
Africa. 

Habitat: Found in iron-bearing waters. 

4. GallioneUa umbellata Beger, 1949. 
{GallioneUa ferrxiginea Palm, Svensk. Bot. 



216 



ORDER I. PSEUDOMONADALES 



Tidskr., 27, 1933, 360; not GaUionella ferru- 
ginea Ehrenberg, Die Infusionthierchen, 
1838, 166; Beger, Ber. d. deutsch. Bot. Ges., 
52, 1949, 9.) 

um.bel.la'ta. L. noun iimhella umbrella; 
M.L. adj. umbellatus umbel-like. 

Five to six cells are formed at the end of 
the stalks before separation. The cells are 
kidnej^-shaped and 1.0 by 2.0 microns in 
size. The stalks then divide into 5 to 6 
branches forming a simple umbel. This proc- 
ess of cell division and growth of branches 
continues until finally the whole mass ap- 
pears composed of umbels. 

Source: From leaf mold found in streams 
in British-Gambia. 

Habitat: Found in tropical, iron-bearing 
streams. 



5. GaUionella infurcata Beger, 1937. 

(Spiro-phyUum sp., Suessenguth, Cent. f. 
Bakt., II Abt., 1927, 69 and 339; Beger, Gas- 
und Wasserfach, 80, 1937, 887; Spirophyllum 
infurcatum Beger, ibid., 889.) 

in.fur.ca'ta. L. prep, in in; L. nonn furca 
fork; M.L. adj. furcatus forked; M.L. adj. 
infurcatus forked. 

Stalks twisted but not branched. Cells 
coccoid, 1 micron in diameter. After fission 
into two cells, they become detached from 
the stalk. 

Source: Found in water basins in the 
Botanical Garden of Miinchen-Nymphen- 
burg. 

Habitat: Found in iron-bearing waters. 



Genus. III. Siderophaciis Beger, 1944- 
(Ber. d. deutsch. Bot. Ges., 61, 1944, 12.) 

Si.de.ro'pha.cus. Gr. noun siderus iron; Gr. noun phacus lentil; M.L. mas.n. Sidero- 
phaciis iron lentil. 

The stalks are horn-shaped, without branches, and do not form twisted bands; they are 
round to ovoid in transverse section. Cells biconcave or rod-like; after division they sepa- 
rate from the stalk. Ferric hydroxide is stored in the stalks. 

The type species is Siderophaciis corneolus (Dorff) Beger. 



1. Siderophaciis corneolus (Dorff, 1934) 
Beger, 1944. (GaUionella corneola Dorff, Die 
Eisenorganismen, Pflanzenforschung, Heft 
16, 1934, 25; Beger, Ber. d. deutsch. Bot. 
Ges., 61, 1944 12.) 

cor.ne'o.lus. L. adj. corneolus horny, firm. 

Stalks 15 to 30 microns long, broader at 



the top than at the base. Three to eight 
stalks arise from a broad holdfast. Cells 
0.6 to 1.0 by 2.5 to 3.0 microns. 

Source: Found in an iron-bearing rivulet 
near Lot-Malmby, Central Sweden; also 
found near Berlin. 

Habitat: Found in iron-bearing waters. 



Genus IV. Nevskia Famintzin, 1892. 
(Bull. Acad. Imp. Sci., St. Petersb., Ser. IV, 34 (X.S. 2), 1892, 484.) 

Nev'ski.a. Neva a river at Leningrad; M.L. fem.n. Nevskia of the Neva. 

Stalked bacteria, the long axis of the rod-shaped cells being set at right angles to the axis 
of the stalk. Stalks lobose, dichotomously branched and composed of gum. Multiplication 
of cells by transverse binary fission. Grow in zoogloea-like masses in water. 

The type species is Nevskia ramosa Famintzin. 



1. Nevskia ramosa Famintzin, 1892. 
(Bull. Acad. Imp. Sci., St. Petersb., S^r. 
IV, 34 (N. S.^), 1892,484.) 

ra.mo'sa. L. adj. ramosus branched. 

Globular, bush-like or plate-like colonies 
of gummy consistency which float upon the 
surface of water. Colonies composed of 



gummy material arranged in dichotomously 
branched stalks arising from a common 
base, with the bacterial cells contained in 
the gum, a single cell at the tip of each 
stalk. At times cells are set free from the 
stalks to start new colonies. 
Rod-shaped cells set with their long axis 



FAMILY VI. SIDEROCAPSACEAE 217 

at right angles to the axis of the broad, lobe- Source: Found in the aquarium in the 



like stalk. Cells 2 by 6 to 12 microns, con- 
taining a number of highly refractile glob- 
ules of fat or sulfur. Multiplication by 



Botanical Garden, St. Petersburg. Similar 
but smaller organisms found b}' Henrici 



binary fission. and Johnson (Jour. Bact., SO, 1935, 63) in a 



Not cultivated on artificial media. 

Note: Nevskia pediculata Henrici and 
Johnson is now regarded as a Lactobacillus. 
See Lactobacillis brevis Bergey et al., syn. apolis. 
Betabacterium vermijonne IMayer. Habitat : Found in water 



jar of water from the lily pond of the Univer- 
sity of Minnesota greenhouse in Minne- 



FAJVIILY VI. SIDEROCAPSACEAE PRIBRAM, 1929.* 

(Tribe Siderocapseae Buchanan, Jour. Bact., 3, 1915, 615; Pribram, Jour. 
Bact., 18, 1929, 377.) 

Si. de.ro. cap. sa'ce.ae. M.L. fem.n. Siderocapsa type genus of the family; -aceae suffix to 
denote a family; M.L. fem.pl.n. Siderocapsaceae the Siderocapsa family. 

Cells spherical, ellipsoidal or bacilliform. Frequently embedded in a thick, mucilaginous 
capsule in which iron or manganese compounds may be deposited. Motile stages, where 
known, are polar flagellate. Free-living in surface films or attached to the surface of sub- 
merged objects. Form deposits of iron and manganese compounds. Autotrophic, faculta- 
tively autotrophic and heterotrophic species are included in the family. Found in fresh wa- 
ter. 

The morphology of the bacteria of this family is best determined after dissolving the 
iron or manganese compounds with weak acids and staining with Schiff's reagent. 

The type genus is Siderocapsa Molisch. 

Key to the genera of family Siderocapsaceae. 

I. Cells surrounded by capsular matter with iron compounds deposited either on the sur- 
face or throughout the capsular material. 

A. Cells coccoid. 

1. Cells in masses in a common capsule. 

Genus I. Siderocapsa, p*. 218. 

2. Cells always in pairs in a gelatinous capsule. 

Genus II. Siderosphaera, p. 220. 

B. Cells ellipsoidal to bacilliform. 

1. Cells heavily encapsulated but do not possess a torus. f 
a. Cells in chains in a gelatinous capsule. 

b. Chains of ellipsoidal cells embedded in a gelatinous capsule, the outlines 
of which follow the form of the cells. 

Genus III. Sideronema, p. 220. 
bb. Rods in pairs or chains in surface films. 

* Manuscript prepared by Prof. Robert S. Breed, Cornell Universitj^, Geneva, New York, 
December, 1953; further revision with the introduction of additional genera and species 
by Prof. Dr. Herbert Beger, Institutfur Wasser-, Boden- und Lufthygiene, Berlin-Dahlem, 
Germanj% March, 1954. 

t The so-called torus is a marginal thickening of a thin capsule. The torus is heavily im- 
pregnated with iron compounds so that the torus of an individual cell looks like the link 
of a chain or, if incomplete, like a horseshoe. 



218 ORDER I. PSEUDOMONADALES 

Genus IV. Ferribacterium, p. 221. 
aa. Coccoid to rod-shaped cells in masses in a gelatinous capsule. Usually show 
an irregular arrangement of cells. 

Genus V. Sideromonas , p. 222. 
2. Cells with a thin capsule with a torus, 
a. Torus completely surrounds the cells. 

Genus VI. Naumanniella, p. 223. 
aa. Torus open at one pole giving the wall the appearance of a horseshoe. 
Genus VII. Ochrobium, p. 225. 
II. Non-encapsulated cells which form deposits of iron compounds in the cell wall, on 
the surface of the cells or in the surrounding medium. 

A. Cells coccoid. 

Genus VIII. Siderococcus , p. 225. 

B. Cells rod-shaped. 

1. Found in neutral or alkaline waters. 

Genus IX. Siderobacter , p. 226. 

2. Found in acid mine wastes. 

Genus X. Ferrobacillus, p. 227. 

Genus I. Siderocapsa Molisch, 1909. 

(Ann. Jard. Bot. Buitenzorg, 2 S^r., Supp. 3, 1909, 29; also see Die Eisenbakterien, 
Jena, 1910, 11.) 

Si.de.ro.cap'sa. Gr. noun siderus iron; L. noun capsa a box; M.L. fem.n. Siderocapsa 
iron box. 

One to many spherical to ellipsoidal, small cells embedded without definite arrangement 
in a primary capsule. The primary capsules may be surrounded by a large secondary cap- 
sule, and these may then be united into larger colonies. Iron compounds are predominantly 
stored on the surface of the primary capsule, and when a secondary capsule is present, it 
is also completely covered. 

The type species is Siderocapsa treubii Molisch. 

Key to the species of genus Siderocapsa. 

I. Several cells in each capsule. 

A. Attached forms. 

1. Cells small; up to 8 in number in each capsule. 

1. Siderocapsa treubii, 

2. Cells larger; up to 100 and more in each capsule. 

2. Siderocapsa major. 

B. Plankton forms. 

1. Primary capsules 3.5 to 9 microns in diameter, each containing 2 to 8 cells. 

3. Siderocapsa coronata. 

2. Primary capsules 10 to 20 microns in diameter, each containing up to 60 or more 
cells. 

4. Siderocapsa eusphaera. 
II. Only one cell in each capsule. Cells always small. 

A. Capsules attached. 

5. Siderocapsa monoeca. 

B. Capsules form unattached iron floes. 

6. Siderocapsa botryoides. 



FAMILY VI. SIDEROCAPSACEAE 



219 



1. Siderocapsa treiibii Molisch, 1909. 

{Siderocapsa Treuhii (sic) Molisch, Ann. 
Jard. Bot. Buitenzorg, 2 Ser., Supp. 3, 1909, 
29; also see Die Eisenbakterien, Jena, 1910, 
11.) 

treu'bi.i. M.L. gen. noun treuhii of Treub; 
named for Prof. Treub, director of the 
Tropical Garden at Buitenzorg, Java. 

Cocci, 0.4 to 0.6 micron in diameter. As 
many as 8 cells may be embedded in zoo- 
gloeal masses surrounded by ferric hy- 
droxide and other iron or manganese com- 
pounds; these masses are 1.8 to 3.6 microns 
in diameter. 

Deposits ferric hydro.xide on the surfaces 
of water plants. 

Regarded by Hardman and Henrici (Jour. 
Bact., 37, 1939, 97) as a heterotrophic organ- 
ism that utilizes the organic radicle of 
organic iron compounds, depositing the iron 
as a waste product on the capsules of the 
colonies. 

Source: Found attached to the roots, root 
hairs and leaves of water plants {Elodea, 
Nymphaea, Sagittaria, Salvinia, etc.) in Java. 

Habitat: Widely distributed in fresh 
water. Epiphytic on submerged plants or 
on other objects. Abundant in alkaline, 
hard-water lakes of the drainage type in 
Minnesota and Wisconsin according to 
Hardman and Henrici {ibid., 103). Absent 
in neutral or acid soft-water lakes of the 
seepage type. 

2. Siderocapsa major Molisch, 1909. 
(Ann. Jard. Bot. Buitenzorg, 2 S^r., Supp. 
3, 1909, 29; also see Die Eisenbakterien, 
Jena, 1910, 13.) 

ma'jor. L. comp.adj. major larger. 

Cells colorless, coccus-like, short rods, 
0.7 by 1.8 microns. A colony may consist of 
100 or more cells in the same mucilaginous 
capsule. 

Similar to Siderocapsa treuhii except that 
the cells are larger and the gelatinous 
capsule is less sharply defined. May be free- 
floating in surface films or may be attached 
to submerged objects. 

Forms intermediate between Siderocapsa 
major and Siderocapsa treuhii have been 
observed by Hardman and Henrici (Jour. 
Bact., 37, 1939, 97). 



Source: Found on the surface of a Spiro- 
gyra sp. near Prague. 

Habitat: Widely distributed in fresh 
water. 

3. Siderocap.sa coronata Redinger, 1931. 
(Arch. f. Hydrobiol., ££, 1931, 410.) 

co.ro.na'ta. L. part. adj. coronatus 
crowned. 

Coccoid cells, about 1.0 micron in diam- 
eter, occurring in the primary capsule in 
groups of 2 to 8. These groups are sur- 
rounded by secondary gelatinous capsules 
which may unite into foamy, irregular 
masses 5 to 10 or more cm in diameter. The 
capsular material contains deposits of iron 
and manganese. Free-floating. Yellowish to 
dark brown in color. 

Source: Found in water from Upper 
Lake, Lunz, Austria. Foamy masses are 
formed in the winter time. Ruttner (Arch, 
f. Hydrobiol., 33, 1937, 167) reports that the 
distribution of this organism in Alpine lakes 
is related to the o.xygen stratification 
therein : it was found most frequently at 
depths of from 17.5 to 27.5 meters, where the 
oxygen range was 0.12 to 0.30 mg per liter. 
4.66 mg per liter was the highest oxygen 
tension at which it was found. 

Habitat: Presumably widely distributed 
in water. 

4. Siderocapsa eusphaera Skuja, 1948. 
(Symbolae Bot. Upsal., 9 (3), 1948, 12.) 

eu.sphae'ra. Gr. prep, eu true; Gr. noun 
sphaera ball, sphere; M.L. noun eusphaera 
a true sphere. 

Cells coccus-shaped, 1 to 2 microns in 
diameter, 2 to 60 and more in a primary 
capsule. The latter are 10 to 20 microns in 
diameter and are surrounded by a large 
secondary capsule up to 50 microns in diam- 
eter. The secondary capsules are united into 
large colonies with a common mucilaginous 
layer. The secondary capsule stores com- 
pounds of iron and manganese. 

Source: Found in lakes in Sweden; found 
in the plankton at levels where the oxygen 
tension is low. 

Habitat: Presumably widely distributed 
in fresh-water lakes. 



220 



ORDER I. PSEUDOMONADALES 



5. Siderocapsa nionoeca Nauniann, 
1922. (Siderocapsa monoica (sic) Naumann, 
Kgl. Svensk. Vetensk. Akad. Handl., I, 62, 
1922, 49.) 

mo.noe'ca. Gr. adj. monus alone, solitary; 
Gr. noun oecus house, dwelling; M.L. adj. 
monoecus solitary dwelling. 

Cells single, coccus-shaped or ellipsoidal, 
0.5 to 0.7 micron in diameter, surrounded 
by a more or less thick layer of iron and 
manganese compounds in which, at least 
when young, a rounded space is kept free. 
The cell may be seen in this clear space. 
Although the cells are found in great num- 
bers in close proximity to each other, they 
are distinctly isolated. Form iron and man- 
ganese deposits on the surface of water 
plants and submerged objects. 



Source: Isolated from the surface of 
Poiamogeton nutans in Sweden. 

Habitat: Found in ponds, rivers and 
waterworks; presumably widely distributed. 

6. Siderocapsa botryoides Beger, 1949. 
(Zent. f. Bakt., I Abt., Orig., 15J^, 1949, 65.) 

bot.ry.o.i'des or bot.ry.oi'des. Gr. adj. 
botryoides like a bunch of grapes. 

Cells coccus-shaped, spherical or ellipsoi- 
dal, 0.6 to 0.8 micron in diameter. With 
the capsule they are 0.8 to 2.0 microns in 
diameter, lying singly only when young, 
later forming spherical to clustered colonies 
up to 0.3 cm long. 

The encrusted colonies form iron or 
manganese floes. 

Source: Found in wells and waterworks 
near Berlin. 

Habitat: Presumably widely distributed. 



Genus II. Siderosphaera Beger, 1944- 
(Ber. d. deutsch. Bot. Ges., 62, (1944) 1950, 7.) 

Si.de.ro.sphae'ra. Gr. noun siderus iron; L. noun sphaera ball, sphere; M.L. fem.n. 
Siderosphaera iron sphere. 

Small, coccoid cells, always occurring in pairs and embedded in a primary capsule. After 
cell division the daughter pairs, with the primary capsules, are surrounded by a new, com- 
mon capsule. This division continues up to the formation of eight pairs and results in a 
round, ball-shaped Gloeocapsa-like stage which stores compounds of iron. A number of these 
balls unite to form larger floes which may lie on the surface of bottom mud in fresh-water 
ditches and swamps. 

The type species is Siderosphaera conglomerata Beger. 



1. Siderosphaera conglomerata Beger, 
1950. (Ber. d. deutsch. Bot. Ges., 62, (1944) 
1950, 7.) 

con.glo.me.ra'ta. L. part. adj. conglomer- 
ates rolled together. 

Cocci, 1.0 to 1.2 microns in diameter, 
each with a sheath about 2.0 microns in 
diameter. These cells divide to form 2, 4 or, 
at times, 8 pairs of cells in a clear, spherical, 
gelatinous colony 8 to 10 microns in diam- 
eter. 

Spherical to ellipsoidal floes containing 



these colonies may be as much as 500 mi- 
crons in diameter. In general appearance 
these floes resemble those formed b}^ Sidero- 
capsa coronata found in the Upper Lake at 
Lunz. When dilute HCl is added, the jelly- 
like colonies may be liberated as the iron 
salts dissolve. Manganese salts are appar- 
ently not present. 

Source: Found in a small ditch near Lunz 
(Austrian Alps). 

Habitat : Found on the surface of mud in 



Genus III. Sideronema Beger, 1941- 
(Zent. f. Bakt., II Abt., 103, 1941, 321.) 
Si.de.ro.ne'ma. Gr. noun siderus iron; Gr. noun yiema thread; M.L. neut.n. Sideronema 
iron thread. 
Coccoid cells occurring in short chains which are enclosed in a gelatinous sheath. The 



FAMILY Vr. SIDEROCAPSACEAE 



221 



cell membrane contains an abundance of ferric hydroxide whereas the sheath is relatively 
devoid of this substance. Non-motile and unattached. Found in iron-bearing waters. 
The type species is Sidcronemn qlobuUfervm Beger. 



1. Sideroiiema globuliferiim Boger, 

1941. (Sideronemn glohulijern (sic) Beger, 
Zent. f. Bakt., II Abt., 103, 1941, 321.) 

glob.u.li.fe'rum. L. divcv.noun cjlob^dus a, 
small sphere, globule; L. v. fero to bear, 
carry; M.L. adj. (/lobulijerus globule-bear- 
ing. 

Cells coccoid, round to egg-shaped, 4.8 
to 5.0 by 6.5 microns. Occur in chains (3 to 
S cells) which are enclosed in a gelatinous 



sheath 1.6 microns thick; the cells in these 
chains are non-confluent. Ferric hydroxide 
is found in the cell membrane but only 
sparingly so in the sheath. Non-motile and 
unattached. 

Source: Found on gla.ss slides submerged 
in spring water near Magdeburg, Germany. 

Habitat: Presumably widely distributed 
in iron-bearing waters. 



Genus IV. Ferribacterium Brussoff, 1916. 

(Brussoff, Cent. f. Bakt., II Abt., .(5, 1916, 547; Sideroderma Naumann, Kungl. Svenska 
Vetenskapsakad. Handl., 62, 1922, 54.) 

Fer.ri.bac.te'ri.um. L. nonn fernnn iron;Gr. dim. noun bacterium a small rod; M.L. 
neut.n. Ferribacterium iron rodlet. 

Rods, with rounded or square ends, usually occurring in pairs, sometimes appearing singly 
or in short chains. Motility occasionally observed; presumably the cells are polar flagellate. 
In most cultures the cells are enclosed in a gelatinous capsule which is ordinarily surrounded 
hy deposits of iron compounds. Produces a pellicle on the surface of liquid media and wa- 
ter. Found in iron- or manganese-bearing water. 

The type species is Ferribacterium duplex Brussoff. 



1. Ferribacterium duplex Brussoft", 
1916. (Brussoff", Cent. f. Bakt., II Abt., ^5, 
1916, 5-i7; Sideroderma duplex Naumann, Kgl. 
Svenska Vetenskapsakad. Handl., 62, 1922, 
55 and 63.) 

du'plex. L. adj. duplex two-fold, double. 

Rods, with rounded ends, 1.2 by 2.5 to 
5.0 microns, occurring usually in pairs, 
sometimes singl}' or in short chains. Re- 
ported as non-motile. Cells enclosed in a 
gelatinous capsule which is ordinarily sur- 
rounded by iron compounds. According to 
Sauer (Inaug. Diss., Kiel, 1934, 33) the cells 
are motile and Gram-negative. 

Peat-infusion agar: In old cultures the 
gelatinous capsule is surrounded by a dark 
sheath, never bj- an iron secretion; the 
sheath is generally ellipsoidal. Irregular 
forms are also found. 

Iron ammonium citrate broth: Pellicle 
scarcely visible, appearing yellow under 
the microscope. 

Iron peptone broth: Produces a barelj- 



visible pellicle which appears yellow under 
the microscope. 

Water: A pellicle is formed which is 
weakly iridescent or of a metallic sheen. 

Aerobic. 

Source: Isolated from an ochre-colored 
sediment from two samples of tap-water 
from Breslau labelled "Schwentniger" and 
"Pirschamer". 

Habitat: Found in iron-bearing waters. 

2. Ferribacterium rectangulare (Nau- 
mann, 1922) Beger, comb. nov. (Sideroderma 
rectangulare Naumann, Kungl. Svenska 
Vetenskapsakad. Handl., 62, No. 4, 1922, 54; 
Sideroderma tenue Naumann, loc. cit.) 

rec.tang.u.la're. L. adj. rectus straight; 
L. adj. angularis angular; M.L. adj. rectan- 
gularis rectangular. 

Rods, with square ends, 0.5 by 3.0 mi- 
crons. Embedded in capsular material in 
pairs. Iron compounds deposited outside 



222 



ORDER I. PSEUDOMONADALES 



the capsules which are found in surface 
films. No motility observed. 

Aerobic. 

Comment: The differences between the 
two species placed by Naumann (loc. cit.) 
in the genus Sideroderma are not very sig- 
nificant. Moreover, as surface-film organ- 



isms, these are so much like F errihacterium 
duplex Brussoff that they clearly belong in 
the same genus. 

Source: Found in the Anebodae region of 
Sweden. 

Habitat : Found in fresh water, in swampy 
ditches and in small streams. 



Genus V. Sideromonas Cholodny, 1922. 

(Cholodny, Ber. d. deutsch. Bot. Ges., Ifi, 1922, 326; also see Die Eisenbakterien, Pflanzen- 

forschung. Heft 4, 1926, 55; Siderothece Naumann, Kungl. Svenska Vetenskapsakad. 

Handl., 62, No. 4, 1922, 18; Siderocystis Naumann, ibid., 42; also see Dorff, Die 

Eisenorganismen, Pflanzenforschung, Heft 16, 1934, 12; and Beger, Ber. d. 

deutsch. Bot. Ges., 62, (1944) 1950, 8.) 

Si.de.ro.mo'nas. Gr. noun sider^ls iron; Gr. noun monas a unit, monad; M.L. fem.n. 
Sideromonas iron monad. 

Short, coccoid to rod-shaped cells each embedded in a rather large, sharply outlined 
capsule. The number of cells may increase within the capsule, and older capsules may unite 
to form larger colonies, the outlines of which are ill-defined. The capsules are impregnated 
with iron or manganese compounds or are completely encrusted with them. 

The type species is Sideromonas confervarum Cholodny. 



1. Sideromonas confervarum Cho- 
lodny, 1922. (Cholodnyi (sic), Ber. d. 
deutsch. Bot. Ges., 40, 1922, 326; also see 
Cholodny, Die Eisenbakterien, Pflanzen- 
forschung, Heft 4, Jena, 1926, 55.) 

con.fer.va'rum. M.L. fem.n. Conferva a 
genus of algae; M.L. gen. pi. noun confer- 
varum of confer vae 

Coccobacteria, 0.5 to 0.6 by 0.8 to 1.0 
micron, occurring in chains embedded in 
gelatinous masses 10 to 100 microns in 
diameter. Chains become visible when the 
gelatinous mass is treated with formalin 
followed by dilute HCl, washed in water 
and stained with gentian violet or carbol- 
fuchsin. No motility observed. 

Form deposits of iron salts within the 
gelatinous mass surrounding the chains. 

Probably facultative autotrophic (Dorff, 
Tabulae Biologicae, 16, 1933, 222). 

Cause the algal cells that are surrounded 
bj^ the zoogloeal masses to become darker 
green than normal. 

Source: Found on the surface of algae 
{Conferva) in water containing iron salts 
near Kiew (Ukraine); also found near 
Berlin, Central and Southern Sweden, 
Hungary and Moravia. 



Habitat: Widely distributed on fresh- 
water green 



2. Sideromonas duplex (Naumann, 
1922) Beger, comb. nov. {Siderocystis duplex 
Naumann, Kungl. Svenska Vetenskap- 
sakad. Handl., 62, No. 4, 1922, 43.) 

du'plex. L. adj. duplex two-fold, double. 

Slender rods with rounded ends, 0.5 by 
1.5 to 3.0 microns, occurring singly or in 
pairs. Embedded in capsules that may fuse 
to form zoogloeal masses. Iron compounds 
impregnate the capsular material. No 
motility observed. 

Comment: The differences between this 
species and Ferribacterium duplex Brussoff 
are slight; cultural studies may show these 
two to be identical. 

Source: Found in the Aneboda region of 
Sweden. 

Habitat: Found on submerged objects in 
swampy ditches and small streams. 

3. Sideromonas vulgaris (Naumann, 
1922) Beger, comb. nov. {Siderocystis vulgaris 
Naumann, Kungl. Svenska Vetenskapsa- 
kad. Handl., 62, No. 4, 1922, 42.) 

vul.ga'ris. L. adj. vulgaris common. 



FAMILY VI. SIDEROCAPSACEAE 



223 



Slender rods measuring 0.5 by 2.5 microns. 
Rods, several to many placed irregularly in 
a gelatinous envelope, form, when old, 
zoogloea-like masses as much as 7.5 microns 
in diameter. The rods are surrounded by 
primary capsules which are impregnated 
with iron compounds and which later fuse. 

Reported by Dorff (Tabulae Biologicae, 
16, 1938, 221) to be autotrophic. 

Comment: The characters of the genus 
Siderocystis, as described by Naumann 
{loc. cit.), do not seem adequate to distin- 
guish it from the genus Sideromonas, estab- 
lished earlier by Cholodny. 

Source: Found in the Aneboda region in 
Sweden. 

Habitat: Forms deposits on submerged 
objects in ditch and river waters. 

4. Sideromonas major (Naumann, 1922) 
Beger, comb. nov. {Siderothece major Nau- 
mann, Kungl. Svenska Vetenskapsakad. 
Handl., 62, No. 4, 1922, 17; Siderothece 
minor Naumann, loc. cit.; Siderocystis 
minor Naumann, ibid., 43.) 

ma'jor. L. comp.adj. major larger. 



Rods broader than those of Sideromonas 
vulgaris, 0.5 to nearly 1.5 by 1.0 to 1.5 mi- 
crons. Each rod is surrounded by a large 
primary capsule; the capsules later fuse 
and form a gelatinous envelope in which 
the cells are irregularly arranged. Form 
zoogloea-like masses up to 10 microns in 
diameter. Iron compounds deposited within 
the capsular substance. 

Possibly autotrophic (Dorff, Talnilae 
Biologicae, 16, 1938, 221). 

Aerobic. 

Comments: While there are some differ- 
ences in the sizes of the organisms placed 
by Naumann in the three different species 
named above, such differences may, in 
reality, not be significant: these differences 
may be due to variations in the nutritive 
value of the water in which each of the 
organisms was growing. 

Source: Found in the Aneboda region in 
Sweden. 

Habitat: Develop concretionary deposits 
(microscopic particles) on submerged ob- 
jects in swampy ditch and river waters; 
also found in wells and pipes in waterworks. 



Genus VI. Naumanniella Dorff, 1934. 
(Die Eisenorganismen, Pflanzenforschung, Heft 16, 1934, 19.) 

Nau.man.ni.el'la. M.L. dim. ending -ella; M.L. fem.n. Naumanniella named for Einar 
Naumann, a Swedish limnologist. 

Cells ellipsoidal or rod-shaped with rounded ends, occurring singly or in short chains; 
the rods may be straight or curved and frequently are constricted in the middle. Each cell 
is surrounded by a small capsule and a marginal thickening (torus) heavily impregnated 
with iron and manganese compounds. Gelatinous capsules of the type found in Siderocapsa 
are absent. Cell division occurs simultaneously with constriction and separation of the 
torus. The species in this genus have not been cultured. Found at the surface and in or on 
the bottom mud of iron-bearing water. 

The type species is Naumanniella neuslonica Dorff. 



Key to the species of genus Naumanniella. 

I. Cells rod-shaped. 
A. Cells occur singly. 

1. Cell diameter greater than 1.2 microns with the torus. 

a. Cells with the torus 1.8 to 3.3 by 4.0 to 10.0 microns. 

1. Naumanniella neustonica. 
aa. Cells with the torus 1.2 to 1.5 by 3.1 to 3.6 microns. 

2. Naumanniella minor. 

2. Cells 1 by 2 microns with the torus. 



224 



ORDER I. PSEUDOMONADALES 



B. Cells occur in chains. 
II. Cells ellipsoidal. 



3. N aunianniella pygtnaea. 

4. Naumanniella catenata. 
6. Naumanniella ellipiica. 



1. Naumanniella nenstonica Dorff, 
1934. (Die Eisenorganismen, Pflanzen- 
forschung, Heft 16, 1934, 21.) 

neus.to'ni.ca. Gr. adj. neustus swimming, 
floating; M.L. adj. neusfonicus of the neus- 
ton (surface film). 

Cells, including the torus, 1.8 to 3.3 by 
4.9 to 10 microns; never curved but may be 
slightly constricted. Without the torus the 
cells measure 2.5 by 6.0 microns. Occur 
singly in the surface film of water, rarely 
on submerged plants. 

Source: Found on the surface of iron- 
bearing water from wells near Freienwalde 
(1931) and Stolzenhagen (1932) in Mark 
Brandenburg; also isolated at Brisbane, 
Australia. 

Habitat: Widely distributed in swamp 
water. 

2. Naumanniella minor Dorff, 1934. 
(Die Eisenorganismen, Pflanzenforschung, 
Heft 16, 1934,21.) 

mi'nor. L. comp.adj. minor smaller. 

Cells, including the torus, 1.2 to 1.5 by 
3.1 to 3.6 microns; occur singly in the form 
of rods which frequently are curved or 
spiral-shaped. The cells are 0.9 by 3.0 mi- 
crons irrespective of the torus. Usually 
found in or on the bottom mud of fresh- 
water ponds and swampy areas. 

Source: Found at Wurms (Rhein) in the 
bottom of a well which contained iron-bear- 
ing water. 

Habitat: Widely distributed in swamp 
water; also found on ore or on the submerged 
leaves of water plants. 

3. Naumanniella pygmaea Beger, 1949. 
(Zent. f. Bakt., I Abt., Orig., 154, 1949, 65.) 

pyg.mae'a. Gr. adj. pygmaeus dwarfish. 
Small, straight rods, with rounded ends, 
1 by 2 microns with the torus. Occur singly. 



Source: Isolated from pipes and deep 
wells of waterworks near Berlin. Found on 
the surface of the gelatinous mass formed 
by Zoogloea filipendula Beger. 

Habitat: Presumably widely distributed. 

4. Naumanniella catenata Beger, 1941. 
(Zent. f. Bakt., II Abt., 103, 1941, 32.) 

ca.te.na'ta. L. part. adj. catenatus in 
chains. 

Cells 0.4 to 0.5 by 4.6 to 5.2 microns; with 
the torus, 1.0 to 1.2 by 4.9 to 5.5 microns. 
Cells elongated or slightly curved with 
thick walls impregnated with iron. After 
division the cells remain connected in 
chains of several to many (3 to 12). These 
cells are joined together in such a manner 
that, because of the iron-impregnated, 
marginal thickenings and the relatively 
clear cells inside, they give the appearance 
of a chain with elongated links. Non-motile 
and unattached. 

Source: Found on glass slides submerged 
in spring water near Magdeburg, Germany. 

Habitat: Presumably widely distributed 
in or on the bottom mud of iron-bearing 
waters. 

5. Naumanniella elliptica Beger, 1949. 
(Zent. f. Bakt., I Abt., Orig., 154, 1949, 63 
and 65.) 

el.lip'ti.ca. Gr. adj. ellipticus defective, 
elliptical. 

Cells ellipsoidal, 2.0 by 2.5 to 3.0 microns, 
with a pronounced torus. 

Source: Found in pipes and deep wells 
of waterworks near Berlin. Found on masses 
of Crenothrix polyspora threads lying on the 
bottom mud. 

Habitat: Presumably widelj' distributed 
in or on the bottom mud of iron-bearing 
waters. 



FAMILY VI. SIDEROCAPSACEAE 



225 



Genus VII. Ochrobium Perfiliev, 1921. 

(Perfiliev, in Wislouch, Bull. Institut Hydrobiol., Russia, 1921; Sideroderma in part, 

Naumann, Kungl. Svenska Vetenskapsakad. Handl., 62, Part 4, (1921) March 20, 

1922, 32; also see Naumann, Zent. f. Bakt., II Abt., 78, 1929, 514.) 

O.chro'bi.um. Gr. noun ochra yellow ochre, iron oxide; Gr. noun bins life, dwelling; 
M.L. neut.n. Ochrobium ochre-dweller. 

Ellipsoidal to rod-shaped cells that are partially surrounded by a marginal thickening 
(torus) that is heavily impregnated with iron. This torus remains open at one end so that 
it resembles a horseshoe. The cells are surrounded b}' a delicate, transparent capsule that 
contains a very small amount of iron. Polar flagellate. Widely distributed in fresh water. 

The type species is Ochrobium tectum Perfiliev. 



1. Ochrobium tectum Perfiliev, 1921. 
(Perfiliev, in Wislouch, Bull. Institut 
Hydrobiol., Russia, 1921; also see Nach- 
richten des Sapropelkommittees, Leningrad, 
1922, 1; and Verhandl. Intern. Verein. f. 
theor. und angew. Limnologie (1925)3, T. 3, 
1927; Sideroderma limneticum Naumann, 
Kungl. Svenska Vetenskapsakad. Handl., 
62, 1922, 32.) 

tec'tum. L. v. tego to cover; L. past part. 
tectus covered. 

Cells small, ellipsoidal to rod-shaped, 0.5 
to 3.0 hj 1.5 to 5.0 microns. Each cell is 
surrounded by a heavily iron-impregnated 
torus which is open at one pole. Pairs of 
cells appear like a pair of horseshoes with 



the open ends together. The cells are cov- 
ered with a delicate outer capsule, and they 
may be united in small colonies. When 
motile, they bear two unequal polar flagella. 

Comment: The cells are much like those 
found in the algal genus Pteromonas, only 
smaller. 

Source: Originally found in the region 
about Leningrad; then found independently 
by Naumann (Zent. f. Bakt., II Abt., 78, 
1929, 514) in Sweden and later by Beger 
(Zent. f. Bakt., I Abt., Orig., 154, 1949, 65) 
in wells of waterworks near Berlin. 

Habitat: Widely distributed iniron-bear- 
ing waters. 



Genus VIII. Siderococcus Dorff, 1934. 
(Die Eisenorganismen, Pflanzenforschung, Jena, Heft 16, 1934 9.) 

Si.de.ro.coc'cus. Gr. noun siderus iron; Gr. noun coccus a berry, sphere; M.L. mas.n. 
Siderococcus iron coccus. 

Cells cocciform and of small size. Lack a gelatinous capsule. Not encrusted with iron 
compounds; these are deposited entirely outside of the cells. 

The type species is Siderococcus limoniticus Dorff. 



1. Siderococcus limoniticus Dorff, 
1934. (Die Eisenorganismen, Pflanzenfor- 
schung, Jena, Heft 16, 1934, 9.) 

li.mo.ni'ti.cus. Gr. noun limon meadow, 
bog; M.L. noun limonitum limonite, a min- 
eral, ferrous iron o.xide; ALL. adj. limon- 
iticus of limonite. 

Cocci 0.2 to 0.5 micron in diameter. No 
evident capsule. Utilize inorganic iron 
compounds and deposit them outside of 
the cells. 

In liquid cultures, the cells produce, on 
a glass slide, a sharply marked zone beneath 



the surface in which iron compounds are 
deposited on the slide. When the iron com- 
pounds are dissolved with dilute HCl, very 
tiny cocci are left on the slide. 

Source: Isolated from limonite deposits 
in a bay of Teufelsee near Freienwalde, 
Austria. Also found in Russian and Swedish 
iron ore deposits as well as in Java, Sumatra 
and Borneo. 

Habitat : Widely distributed in swamps 
and lakes where limonite deposits are 
forming. 



226 



ORDER I. PSEUDOMONADALES 



2. Siderococcus communis Dorff, 1934. 
(Die Eisenorganismen, Pflanzenforschung, 
Jena, Heft 16, 1934, 9.) 

com.mu'nis. L. adj. communis common. 

Cocci to short rods, 0.4 to 1.0 micron in 
diameter, occurring singly or in chains. No 
capsules observed. Utilize organic iron 
compounds (ferrous ammonium citrate) 
and produce precipitates of ferric oxide. 



Do not grow in water containing inorganic 
iron compounds such as iron carbonate. Do 
not grow on glass slides submerged in w^ater 
containing organic iron compounds but are 
found in the precipitate that is formed. 

Source: Found in many European coun- 
tries and in North America. 

Habitat: Widely distributed in water 
containing organic iron compounds. 



Genus IX. Siderobacter Nauinann, 1922. 
(Kungl. Svenska Vetenskapsakad. Handl., 62, No. 4, 1922, 55.) 

Si.de.ro.bac'ter. Gr. noun siderus iron; M.L. noun bacter the masculine form of the Gr. 
neut. n. hactrum a small rod; M.L. mas.n. Siderobacter iron rodlet. 

Cells bacilliform with rounded ends; occur singly, in pairs or in short chains or are united 
to form colonies. Lack a gelatinous capsule. Iron or manganese compounds are deposited 
on the surfaces or in the membranes of the cells; the deposit may also be entirely outside 
of the cells. Flagellated cells may occur. Found in neutral or alkaline waters. 

The type species is Siderobacter linearis Naumann. 

Key to species of genus Siderobacter. 

I. Cells less than 1.0 micron in diameter. Found on the surface of zoogloeal masses. 

A. Cells less than 0.5 micron in diameter. 

1. Siderobacter gracilis. 

B. Cells 0.8 micron in diameter. 

2. Siderobacter hrevis. 
II. Cells 1.0 micron or greater than 1.0 micron in diameter. 

A. Cells 1.0 micron in diameter. 

3. Siderobacter linearis. 

B. Cells greater than 1.0 micron in diameter. 

1. Cells in pairs and 1.5 microns in diameter. 

4. Siderobacter duplex. 

2. Cells 2.5 microns in diameter. Participate in the formation of iron and lime 
concretions of macroscopic size. 

5. Siderobacter latus. 



1. Siderobacter gracilis Beger, 1949. 
(Zent. f. Bakt., I Abt., Orig., ISJt, 1949, 65.) 

gra'ci.lis. L. adj. gracilis slim, slender. 

Cells 0.4 by 3.0 microns. Encrusted cells 
are 5.0 to 7.0 microns long. Occur singly. 
Participate in the formation of deposits of 
iron compounds. 

Source: Found on the surface of masses of 
Zoogloea filipendula. This species formed 
thick coatings on the walls of two wells 
supplying rapid sand filters near Berlin, 
Germany. The filters required frequent 
washing because the coatings were easily 
detached. 

Habitat: Found in the cool waters of deep 
wells. 



2. Siderobacter brevis Beger, 1949. 
(Zent. f. Bakt., I Abt., Grig., 1S4, 1949, 65.) 
bre'vis. L. adj. brevis short. 

Cells, 0.8 to 1.0 by 3.0 to 4.0 microns, 
usually occurring singly. Participate in the 
formation of deposits of iron compounds. 

Source : Found on the surface of masses of 
Zoogloea filipendula. This species formed 
thick coatings on the walls of two wells 
supphdng rapid sand filters near Berlin, 
Germany. The filters required frequent 
washing because the coatings were easily 
detached. 

3. Siderobacter linearis Naumann, 1922. 



FAMILY VI. SIDEROCAPSACEAE 



227 



(Kungl. Svenska Vetenskapsakad. Handl., 
62, 1922, 55.) 

li.ne.a'ris. L. adj. linearis linear. 

The type species of genus Siderobacter 
Naumann. 

Cells 1.0 by 5.0 microns after the encrust- 
ing iron compounds have been dissolved 
away with dilute HCl. Opaque, encrusted 
cells, 1.2 b}- 7.0 microns. Always occur 
singl}' in contrast to the larger-celled 
Siderobacter duplex, where the cells occur in 
pairs. 

Source: Found in the Aneboda region in 
Sweden. 

Habitat: Found in surface films and on 
submerged objects. 

4. Siderobacter duplex Naumann, 1922. 
(Kungl. Svenska Vetenskapsakad. Handl., 
62, No. 4, 1922, 55.) 

du'plex. L. adj. duplex two-fold, double. 



Cells, 1.5 by 3.5 microns after encrusting 
iron compounds are removed with dilute 
HCl, occurring in pairs. 

Source: Found in the Aneboda region in 
Sweden. 

Habitat: Found in surface films on the 
water of swamps and small streams. 

5. Siderobacter latus Beger, 1941. 
(Zent. f. Bakt., I Abt., Orig., 154, 1949, 63 
and 66.) 

la'tus. L. adj. latus broad. 

Straight or occasionally curved cells, 2.5 
b}^ 6.0 to 15.0 microns, usually occurring 
singly. Participate in the formation of iron 
and lime concretions. 

Source: Found on concretions on the 
brick walls of two wells suppljang a rapid 
sand filter near Berlin, Germany. 

Habitat : Found in the cool waters of deep 
wells. 



Genus X. Ferrobacillus Leathen and Braley, 1954* 
(Bact. Proc. 54th General Meeting, Soc. of Amer. Bact., 1954, 44.) 

Fer.ro. ba.cil'lus. L. noun /errum iron, here meaning ferrous iron; L. dim. noun bacillus 
a small rod; M.L. noun Ferrobacillus ferrous-iron rodlet. 

Short, plump, rod-shaped cells occurring singly and in pairs, seldom in chains; the cells 
are not united to form colonies. O.xidize ferrous iron to the ferric state in acid environments. 
Optimum reaction, pH 3.5. 

The type species is Ferrobacillus ferrooxidans Leathen and Braley. 



1. Ferrobacillus ferrooxidans Leathen 
and Braley, 1954. (Ferrous iron oxidizing 
bacterium, Leathen, IMcIntyre and Braley, 
Bact. Proc. 52nd General Meeting, Soc. of 
Amer. Bact., 1952, 15; also see Leathen, 
Braley and Mclntj're, Appl. Microbiol., 1, 

1953, 65; Leathen and Braley, Bact. Proc. 
54th General Meeting, Soc. of Amer. Bact., 

1954, 44.) 

fer.ro.o'xi.dans. L. noun ferruni iron; 
Gr. adj. oxys sharp, acid; M.L. v. oxido to 
oxidize or make acid; M.L. part. adj. fer- 
rooxidans iron-oxidizing. 

Rods 0.6 to 1.0 by 1.0 to 1.6 microns. 
Motile, presumably polar flagellate. Gram- 
negative. 

Ferrous iron-silica gel : Colonies are small 
and raised with irregular margins. Young 
colonies are glistening and tan, but gradu- 



ally become granular and brown with 
oxidizing iron. A tan to brown area of 
oxidized iron is frequently found around the 
colony. 

Liquid ferrous iron medium (Leathen, 
Mclntyre and Braley, Science, 114, 1951, 
280): Rapidly oxidized; forms a precipitate 
of ferric hydroxide or basic ferric sulfate. 

Acid thiosulfate liquid medium: Not 
oxidized. 

Optimum reaction, pH 3.5. O.xidation 
retarded below pH 2.2 and above pH 4.6. 

Optimum temperature, between 15° 
and 20° C. 

Strictly autotrophic. Derives energy by 
the o.xidation of ferrous iron to the ferric 
state. Utilizes the CO2 of the atmosphere 
as a source of carbon. 

Aerobic. 



*Description of genus and species prepared by Wm. W. Leathen, Mellon Institute, Pitts- 
burgh, Pennsylvania. 



228 ORDER I. PSEUDOMONADALES 

Distinctive characters: By catalytic ac- of even minute traces of ferrous iron medium 

tion, this species increases by several fold to an acid thiosulfate medium may cause 

the amount of sulfuric acid normally formed decomposition of the thiosulfate, evidenced 

by the atmospheric oxidation of pyritic by the development of turbidity due to the 

materials found in bituminous coal seams formation of colloidal sulfur; this purely 

and associated rock strata. chemical reaction involving thiosulfate 



maj^ easily be misinterpreted as a bacterial 
oxidation of this same substrate. 
Source: Isolated from bituminous coal 



Comment: This organism closely resem 
bles Thiobacillus ferrooxidans and may, in 
fact, be identical with it. However Temple 
and Colmer (Jour. Bact., 59, 1950, 317) 
report that Thiobacillus ferrooxidans oxi- "^^^« drainages and from waters receiving 
dizes thiosulfate while Leathen and Braley ^^^^ discharges. 

(op. cit., 1954, 44) report that Ferrobacillus Habitat: Indigenous to bituminous coal 

ferrooxidans does not oxidize thiosulfate. regions. Frequently form relatively hard 
Thelatter workers (personal communication, granules of ferric iron in which many 
May, 1954) further report that the transfer bacteria are entrapped. 



FAMILY VII. SPIRILLACEAE MIGULA, 1894. 

(Migula, Arb. Bact. Inst. Karlsruhe, 1, 1894, 237; Spirillobacteriaccae Orla-Jensen, 
Jour. Bact., 6, 1921, 264.) 

Spi.ril.la'ce.ae. M.L. neut.n. Spirillum type genus of the family; -aceac ending to denote 
a family; M.L. fem.pl.n. Spirillaceae the Spirillum family. 

Cells simple, curved or spirally twisted rods. These frequently remain attached to each 
other after transverse division to form chains of spirally twisted cells. Cells are rigid and 
usually motile by means of a single flagellum (rarely two) or a tuft of polar flagella. Gram- 
negative. Frequently oxidative in their physiology. Aerobic or facultatively anaerobic, 
although a few strict anaerobes occur among the vibrios (Desulfovibrio and Vibrio). Largely 
water forms, although some are parasitic or pathogenic on higher animals and man. 

Key to the genera of family Spirillaceae. 

I. Curved, vibrio-like rods that are rarely united into a complete ring. 

A. Cells curved; rods never united at the end into a ring-shaped cell. Usually possess 
a single, polar flagellum. 

1. Curved rods that are not known to attack cellulose. 

a. Aerobic to anaerobic, heterotrophic vibrios. 

Genus I. Vibrio, p. 229. 
aa. Anaerobic, facultatively autotrophic vibrios that produce hydrogen sulfide 
or methane. 
b. Reduce sulfates to hydrogen sulfide. 

Genus II. Desulfovibrio, p. 248. 
bb. Reduce carbon dioxide to methane. 

Genus III. Methanobacterium, p. 250. 

2. Curved rods that attack cellulose. 

a. Vibrio-like cells. 

Genus IV. Cellvibrio, p. 250. 
aa. Pointed, sickle-shaped cells. 

Genus V. Cellfalcicula, p. 252. 

B. Curved rods that join ends to form a complete ring. 

Genus VI. Microcyclus, p. 253. 



FAMILY VII. SPIRILLACEAE 229 

II. Crescent-shaped to spiral cells that are frequently united into spiral chains of cells. 

A. Cells not embedded in zoogloeal masses. 

1. Spiral cells with polar flagellation. 

a. Possess a tuft of polar flagella. 

Genus VII. Spirillum, p. 253. 
aa. Possess a single, polar flagellum. 

Genus VIII. Paraspirillvm, p. 257. 

2. Crescent-shaped cells with a tuft of flagella attached to the middle of the concave 
side of the cell. 

Genus IX. Selenomonas, p. 258. 

B. Crescent- to spiral-shaped cells embedded in a spherical mass of jelly. Found in 
fresh water. 

Genus X. Myconostoc, p. 260. 

Genns I. Vibrio Miiller, 1773 * 

(Miiller, Vermium terrestrium et fluviatilum, 1, 1773, 39; Pacinia Trevisan, Atti d. Accad. 
Fisio-Medico-Statistica in Milano, Ser. 4, 3, 1885, 83; Microspira Schroeter, 
in Cohn, Kryptogamen-Flora von Schlesien, 3, 1, 1886, 168.) 

Vib'ri.o. L. v. vibro to move rapidly to and fro, to vibrate; M.L. mas.n. Vibrio that 
which vibrates. 

Cells short, curved, single or united into spirals. Motile by means of a single, polar flagel- 
lum which is usually relativel}^ short; rarely two or three flagella in one tuft. Grow well and 
rapidly on the surfaces of standard culture media. Heterotrophic organisms varying greatly 
in their nutritional requirements. Aerobic, facultative anaerobic and anaerobic species. 
Widely distributed as saprophytic forms in salt- and fresh-water and in soil; also occur as 
parasites and as pathogens. 

See Genus I, Pseudomonas, of Family IV, Pseudomonadaceae , for a discussion of the border- 
line between the genus Vibrio and the genus Pseudomonas. 

Few comparative studies have been made on the species in this genus; it is therefore 
impossible to prepare a really satisfactory differential key. 

The type species is Vibrio comma (Schroeter) Winslow et al. 

Kerj to the species of genus Vibrio. 

I. Aerobic species. 

A. Produce acid but no gas from glucose and usually from other sugars (one lumines- 
cent, one halophilic and several agar-digesting species fail to produce acid from 
glucose) . 

1. Not luminescent, not able to digest agar and do not attack benzene ring com- 
pounds or o.\idize oxalates so far as known, 
a. Found in fresh water or in the body fluids of animals, including man. 
b. Liquefy gelatin. 

c. Indole produced. 

d. Nitrites produced from nitrates. 
6. Milk not coagulated. 
f. Cause of cholera. 

1. Vibrio comma. 

ff. Cholera-like vibrio from fresh water. 

2. Vibrio herolinensis. 

* Revised by Prof. Robert S. Breed, Cornell University, Geneva, New York, January, 
1954; the section covering the microaerophilic and anaerobic animal pathogens was re- 
viewed by Dr. E. V. Morse, College of Agriculture, University of Wisconsin, Madison, 
Wisconsin, May, 1955. 



230 ORDER I. PSEUDOMONADALES 

ee. Milk coagulated. 

3. Vibrio metschnikovii . 
dd. Nitrites not produced from nitrates. 

4. Vibrio proteus. 
cc. Indole not produced. 

d. Found in the human buccal cavity. 

5. Vibrio sputigenus. 
dd. Cause of abscesses in the African toad. 

6. Vibrio xenopus. 
bb. Does not liquefy gelatin. 

7. Vibrio leonardii. 

aa. Require sea-water or heavy brine media for growth on fresh isolation, 
b. Isolated from sea water. 

c. A diffusible dark brown pigment is usually produced in gelatin 
media. 

8. Vibrio marinopraesens . 

cc. A buff -colored pigment is produced on sea-water agar. No diffusible 
pigment produced. 

9. Vibrio phytoplanktis . 
bb. Found growing in brines. 

c. Acid from glucose. 

10. Vibrio costicoliis. 
cc. No acid from glucose. 

11. Vibrio halonitrificans. 

2. Luminescent, digest agar, attack benzene ring compounds or oxidize oxalates, 
a. Produce luminescence especially on neutral media containing sea water or 
the equivalent salt content, 
b. Gelatin liquefied. 

c. Require alkaline sea water or equivalent media for growth, 
d. Optimum growth temperature, between 25° and 28° C. 

12. Vibrio himinosus. 

dd. Optimum growth temperature, between 30° and 32° C. 

13. Vibrio indicus. 

cc. Found in fresh water and in intestinal contents. 

14. Vibrio albensis. 
bb. Does not liquefy gelatin. 

15. Vibrio pierantonii. 
aa. Not as above. 

b. Digest agar either actively or at least soften it. 
c. Found in soil and in rotting organic matter, 
d. Decomposes both cellulose and agar. 

16. Vibrio agarliqvefaciens. 
dd. Liquefies agar only. 

17. Vibrio andoii. 
cc. Found in sea water with rotting algae. 

d. Nitrites produced from nitrates. 

e. Colonies on agar are white to gray. 

18. Vibrio beijerinckii. 

ee. Colonies on agar are pale yellow becoming bright yellow 
then pale brown. 

19. Vibrio fuscus. 



FAMILY VII. SPIRILLACEAE 231 

dd. Nitrites not produced from nitrates. 

20. Vibrio granii. 
bb. Not as above. 

c. Soil organisms that are known to attack benzene ring compounds, 
d. Soil organism that attacks naphthalene. 

21. Vibrio neocistes. 

dd. Soil organism that attacks phenol and m-cresol. 

22. Vibrio cyclosites. 

cc. Soil organisms that are known to attack oxalates. 

d. Grows well on calcium oxalate agar. White colonies. 

23. Vibrio oxaliticus. 

dd. Forms film on bottom of liquid oxalate media. Rose-red to 
blood-red chromogenesis on oxalate agar. 

24. Vibrio extorquens. 
B. Do not attack carbohydrates. 

1. Soil organism that is known to attack naphthalene. 

25. Vibrio cuneatus. 

2. Not as above. 

a. Do not liquefy gelatin, 
b. From fresh water. 

26. Vibrio percolans. 

bb. Requires sea-water media for growth on fresh isolation. 

27. Vibrio adapiaius. 
aa. Liquefy gelatin. 

b. Causes a disease in fresh-water fishes. 

28. Vibrio piscium. 

bb. Requires sea-water media for growth on fresh isolation. 

29. Vibrio hyphalus. 

II. Anaerobic to microaerophilic species (all parasitic, normally pathogenic). 
A. Microaerophilic species that are pathogenic to warm-blooded animals. 

1. Cause of abortion in cattle and sheep. 

30. Vibrio fetus. 

2. Not as above. 

a. Cause of swine dysentery. 

31. Vibrio coli. 

aa. Cause of dysentery in cattle and related animals. 

32. Vibrio jejuni. 
B. Strict anaerobes. 

a. Produces gas and bad odors in protein media. 

33. Vibrio niger. 

aa. Does not produce gas and bad odors in protein media. 

34. Vibrio sputorum. 

1. Vibrio comma (Schroeter, 1886) wiede, Rogers and Smith, Jour. Bact., 5, 
Winslow et al., 1920. (Kommabacillus, 1920 204.) 

Koch, Berliner klin. Wochenschr., ^i, 1884, „^/,„„ n- ^ ^„ „^„.^„ 

o • -77 77 • • r, r. • com'ma. ur. comma a comma. 

479; bpinllum cholerae asiaticae Zopf, Die , , , , 

Spaltpilze, 3 Aufl., 1885, 69; Microspira Slightly curved rods, 0.3 to 0.6 by 1.0 to 

comma Schroeter, in Cohn, Kryptogamen ^.0 microns, occurring singly and in spiral 

Flora V. Schlesien, 3, 1, 1886, 168; Vibrio chains. Cells may be long, thin and delicate 

cholerae Neisser, Arch. f. Hyg., 19, 1893, 199; or short and thick. May lose their curved 

Winslow, Broadhurst, Buchanan, Krum- form on artificial cultivation. Motile, 



232 



ORDER I. PSEUDOMONADALES 



possessing a single polar flagellum. Gram- 
negative. 

Gelatin colonies: Small, yellowish white. 

Gelatin stab: Rapid, napiform liquefac- 
tion. 

Agar colonies: Circular, whitish brown, 
moist, glistening, translucent, slightlj^ 
raised, entire. 

Agar slant: Brownish gray, moist, glisten- 
ing. 

McConkey's medium: Good growth, 
colonies colorless when young, soon pinkish, 
medium becomes darker red. 

Broth: Slightly turbid, with fragile, 
wrinkled pellicle and flocculent precipitate. 

Peptone water: Characteristic rapid 
growth, chiefly at surface, where, after 6 
to 9 hours, a delicate membrane is formed; 
little turbidity, deposit apparently derived 
from pellicle (Topley and Wilson, Princip. 
Bact. and Immun., 2nd ed., 1936, 388). 
Readily isolated from the surface film of 
0.1 per cent peptone water. 

Litmus milk: Alkaline at the top and 
slightly acid at bottom; generally not 
coagulated; peptonized; reduced. 

Potato: Dirty white to yellowish, moist, 
glistening, spreading growth. 

Blood serum: Abundant growth, some- 
times slow liquefaction. 

Blood agar: The blood pigment is di- 
gested forming a greenish zone around 
colonies; a true soluble hemolysin is not 
formed (the El Tor vibrio also digests 
blood pigment but in addition produces a 
soluble hemolysin; otherwise it is said to 
be indistinguishable from the typical 
cholera vibrio) . 

Indole produced. 

Cholera-red reaction, which depends on 
production of indole and reduction of 
nitrates, is positive. 

Hydrogen sulfide produced. 

Acid but no gas from glucose, fructose, 
galactose, maltose, sucrose and mannitol. 
Slowly from glycerol. Does not attack 
lactose, inulin or dulcitol. 

Group I of Heiberg (Classification of 
Vibrio cholerae and Cholera-like Vibrios. 
Copenhagen, 1935) ferments mannose and 
sucrose but not arabinose. 

Hydrolyzes starch actively in alkaline 
media. 



Nitrites produced from nitrates. 

High alkali but low acid tolerance: 
optimum pH, between 7.6 and 8.0; for 
isolation on Dieudonne's medium, pH 9.0 
to 9.6. 

Aerobic, grows best in abundant oxygen; 
under strict anaerobiosis may fail to grow 
altogether. 

Optimum temperature, 37° C. Maximum, 
42° C. Minimum, 14° C. 

Source: Isolated from the intestinal 
contents of cholera patients in Egypt and 
India. 

Habitat: Found in the intestinal contents 
of cholera patients and carriers. 

The relationships existing among the 
cholerigenic and non-pathogenic water 
vibrios, although studied intensively, have 
not yet been completely defined. As a 
working scheme, based on somatic (O) and 
flagellar (H) antigen studies, Gardner and 
Vankatraman (Jour. Hyg., 35, 1935, 262- 
282) suggest the one shown in the graph 
on the following page. 

Linton (Bact. Rev., 4, 1940, 275) has out- 
lined a classification of the vibrios based 
upon their protein and polysaccharide struc- 
tures. Using chemical methods, it was found 
that one polysaccharide and one protein 
was commonly obtained from each strain 
of vibrio; when exceptions occurred, it was 
invariably noted that the strain was under- 
going dissociation. Given a single protein 
and polysaccharide in each vibrio, it was 
possible to divide the strains into six groups, 
which were numbered in the order of their 
discovery as shown in the table. 

A chemical grouping of the cholerigenic 
and water vibrios. 



Group 


Protein Type 


Polysaccharide 
Type 




I 


I 


I 




II 


I 


II 




III 


II 


II 




IV 


II 


I 




V 


II 


III 




VI 


I 


III 



The strains of Groups I and II possess 
the same protein and different polysaccha- 



FAMILY VII. SPIRILLACEAE 



233 



Cholera group of vibrios. 
(Biochemically similar. Common H antigen.) 



0-sub-group I, 



Non-hemolytic 
(goat cells). 
Cholera vibrios. 
Types — original , 
variant and mid- 
dle. 



Hemolytic (goat 

cells) . 

El Tor vibrios. 

Types — original 

and variant (?mid- 

dle). 



I 
O sub-groups II, III, IV, V, VI and indi- 
vidual races (mostly hemolytic). Para- 
cholera, cholera-like, and some El Tor 
vibrios. 



(Types within sub-groups underlined.) 



rides. These are derived from cases of chol- 
era and have the serological and biochemical 
characteristics of 0-Group I, Vibrio chol- 
era. Group I strains are more common than 
those of Group II, which have, however, 
been isolated from epidemics with a high 
mortality. The phospholipid fraction is 
common to both tj^pes when isolated in the 
early part of an epidemic but is not found 
in strains of other groups. The harmless 
water vibrios, which are so heterogeneous 
serologically (Taylor and Ahuja, Indian 
Jour. Med. Res., 26, 1938, 8-32), form a 
single chemical group with a homogeneous 
structure. They fall into Group III, which 
differs in its protein structure from the 
authentic cholera vibrios and which re- 
sembles Group II in its polysaccharide. The 
vibrios of Group IV, which came from El 
Tor and from chronic vibrio carriers, are 
believed, on epidemiological grounds, to 
be harmless, although serological methods 
have failed to distinguish them from chol- 
erigenic vibrios. Group V, which, like III 
and IV, contains protein II, consists, like 
Group IV, of strains from chronic vibrio 
carriers. Group VI strains are only rarely 
isolated in nature, and representatives of 
this group are generally found among col- 
lections of old laboratory strains. They 
appear to be the result of polysaccharide 
variation from Group I after long-con- 
tinued growth on artificial media. 

2. Vibrio berolinensis Xeisser, 1893. 
(Arch. f. Hyg., 19, 1893, 200.) 



be.ro.li.nen'sis. M.L. Berolinum place 
name, Berlin; M.L. adj. berolinensis of 
Berlin. 

Curved rods, somewhat smaller than those 
of Vibrio comma, frequently occurring in 
pairs. Pleomorphic. Motile by means of a 
single, polar flagellum. Gram-negative. 

Gelatin colonies: Small, grayish, slightly 
granular, fragmented; very slow liquefac- 
tion. 

Gelatin stab: Slow, napiform liquefaction. 

Agar slant: Grayish yellow, moist, glis- 
tening growth. 

Broth: Turbid, with gray pellicle. 

Litmus milk: No coagulation, no acid. 

Potato: Brownish streak. 

Indole produced. 

Nitrites produced from nitrates. 

Not pathogenic for mice, pigeons or 
guinea pigs. 

Aerobic, facultative. 

Optimum temperature, 37° C. Minimum, 
above 10° C. Maximum, less than 60° C. 

Source: Isolated from filtered Spree river 
water. 

Habitat: Presumably widely distributed 
in polluted water. 

3. Vibrio metschnikovii GamaMia, 1888. 
{Vibrio metschnikovi (sic) Gamaleia, Ann. 
Inst. Past., 2, 1888, 482.) 

metsch.ni.ko'vi.i. Named for Metsch- 
nikoff, a Russian bacteriologist; M.L. mas. 
gen.n. metschnikovii of Metschnikoff. 

Curved rods, somewhat shorter and 
thicker than those of Vibrio comma. Long, 



234 



ORDER I. PSEUDOMONADALES 



slender chains of cells are formed in old 
cultures. Motile by means of a single, polar 
flagellum. In the animal body the cells are 
nearly coccoid. Gram-negative. 

Gelatin colonies: Like those of Vibrio 
comma. 

Gelatin stab: Rapid, napiform liquefac- 
tion. 

Agar slant: Yellowish, plumose, moist, 
glistening growth. 

Broth: Turbid, with thin, white pellicle. 

Litmus milk: Acid, coagulated (eighth 
day) ; not peptonized. 

Potato: Delicate, brownish growth. 

Indole produced. 

Nitrites produced from nitrates. 

Aerobic, facultative. 

Optimum temperature, 37° C. Maximum, 
less than 45° C. 

Pathogenic for pigeons, fowls and guinea 
pigs. 

Source: Isolated from fowl dead of a chol- 
era-like disease. 

Habitat: Found in the intestinal contents 
of chickens, pigeons and other animals suf- 
fering from a cholera-like disease. 

4. Vibrio proteus Buchner, 1885. (Kom- 
mabacillus der cholera nostras, Finkler and 
Prior, Deutsche med. Wochenschr., 1884, 
632; Buchner, Sitzungsber. d. Gesel. f. 
Morph. u. Physiol., Miinchen, Heft 1, 1885, 
10.) 

pro'te .us. Gr. noun Proteus a sea-god who 
could change his form; M.L. mas.n. Proteus 
a generic name. 

Description supplemented by material 
taken from Lehmann and Neumann (Bakt. 
Diag., 7 Aufl., 2, 1927, 541). 

Curved rods, 0.4 to 0.6 by 2.4 microns, 
often pointed at both ends. Motile by means 
of a single, polar flagellum. Gram-negative. 

Gelatin colonies: Small, gray, circular, 
granular, entire; rapid liquefaction with 
the formation of large craters. 

Gelatin stab: Rapid, saccate liquefaction. 

Agar slant: Dirty grayish, plumose 
growth. 

Broth: Turbid, with fetid odor. 

Litmus milk: Slightly acid; coagulated; 
peptonized. 

Potato: Grayish, slimy layer. 



Indole not produced; indole reaction weak 
(Lehmann and Neumann). 

Hydrogen sulfide production very slight. 

Gas not produced from glucose. 

Nitrites not produced from nitrates. 

Aerobic, facultative. 

Optimum temperature, 30° C. 

Source: Isolated from feces of patients 
suffering from cholera nostras (gastroen- 
teritis) . 

Habitat: Found in the intestinal contents 
in cholera nostras and cholera infantum. 

5. Vibrio sputigenus (Migula, 1900) 
Bergey et al., 1923. (Vibrio aus Sputum, 
Brix, Hyg. Rundschau, 4, 1894, 913; Micro- 
spira sputigena Migula, Syst. d. Bakt., 2, 
1900, 981; Bergey et al.. Manual, 1st ed., 
1923, 80.) 

spu.ti'ge.nus. L. noun sputum spit, spu- 
tum; Gr. v. gennao to bear; M.L. adj. sputi- 
genus sputum-borne. 

Slightly curved rods, about the same 
size and form as those of Vibrio comma, 
occurring singly, occasionally three or four 
in a chain. Motile by means of a single, polar 
flagellum. Gram-negative. 

Gelatin colonies: Small, circular, slightly 
granular, yellowish, becoining brownish. 

Gelatin: Crateriform liquefaction. 

Agar slant: Grayish white, moist. 

Broth: Turbid, no pellicle formed. 

Litmus milk: Acid; coagulated. 

Potato: Thin, gray layer, spreading. 

Indole not produced. 

Nitrites not produced from nitrates. 

Aerobic, facultative. 

Optimum temperature, 37° C. 

Source: Isolated from sputum. 

6. Vibrio xenopus Schrire and Green- 
field, 1930. (Trans. Roy. Soc. So. Africa, 
17, 1930, 309.) 

xe'no.pus. Gr. adj. xenus alien, strange; 
Gr. noun pus, podis a foot; M.L. mas.n. 
Xenopus strange foot, a genus of toads. 

Spiral forms, occurring singly and in 
pairs. Non-motile. Gram-negative. 

Gelatin stab: Slow, crateriform liquefac- 
tion. 

Agar colonies: Small, white, glistening, 
slimy, entire. 



FAMILY VII. SPIRILLACEAE 



235 



Agar slant: Grayish white, slimy, entire 
growth. 

Broth: Turbid with flocculent sediment. 

Litmus milk: Unchanged. 

Potato: Not reported. 

Indole not produced. 

Blood serum peptonized. 

Starch not hydrolyzed. 

Acid from glucose, fructose, maltose, 
glycerol and sorbitol. 

Nitrites produced slowly from nitrates. 

Aerobic, facultative. 

Optimum temperature, 37° C. 

Source: Isolated from an abscess of the 
pectoral muscle of an African toad. 

7. Vibrio leonardii Mdtalnikov and 
Chorine, 1928. (Ann. Inst. Past., Ji2, 1928, 
1647.) 

le.o.nar'di.i. M.L. gen. noun leonardii of 
Leonard; named for A. G. Leonard. 

Curved rods with rounded ends, 0.5 to 
1.0 by 2.0 to 3.0 microns. Motile by means 
of 1 to 3 polar flagella. Gram-negative. 

Gelatin stab: No liquefaction. 

Agar colonies: Small, transparent, circu- 
lar, having a characteristic odor. 

Broth: Turbid, with thin pellicle. 

Litmus milk: No coagulation, acid, with 
reduction of litmus. 

Potato: Slight, colorless growth. 

Coagulated blood serum not liquefied. 

Indole not produced. 

Hydrogen sulfide produced. 

Acid and gas from glucose, fructose, ga- 
lactose, lactose, sucrose and mannitol. No 
acid or gas from maltose or glycerol. 

Nitrites produced from nitrates. 

Aerobic, facultative. 

Optimum temperature, 30° C. 

Habitat: Highly pathogenic for insects 
such as Galleria mellonella L. (wax moth) 
and Pyrmista nubialis Hiibn. (European 
corn borer). 

8. Vibrio niarinopraesens ZoBell and 

Upham, 1944. (Bull. Scripps Inst, of Ocean- 
ography, Univ. Calif., 5, 1944, 256.) 

ma.ri .no.prae'sens. L. adj. marinus of the 
sea; L. part. adj. praesens present; M.L. 
adj. marinopraesens present in the sea. 

Curved rods, 0.4 to 0.5 by 1.2 to 2.4 mi- 



crons, occurring singly and in spiral chains. 
Polar staining. Motile by means of one or 
two polar flagella. Gram-negative. 

Note: All differential media except the 
fresh-water broth, litmus milk and potato 
were prepared with sea water. 

Gelatin colonies: Circular, 1 mm in di- 
ameter, dense center, brown discoloration 
of gelatin. 

Gelatin stab: Stratiform above, infundi- 
buliform below; complete liquefaction in 
5 days; brown discoloration of gelatin. 

Agar colonies: Convex, circular, 0.5 mm 
in diameter, entire, translucent. 

Agar slant: Abundant, filiform, glisten- 
ing, butyrous growth with no pigment. 

Sea-water broth: Heavy turbidity; slight 
viscid sediment; surface ring. 

Fresh-water broth: No visible growth. 

Litmus milk: Completely decolorized. 

Potato: No visible growth. 

Indole not produced. 

Hydrogen sulfide rapidly produced. 

Acid but no gas from glucose and maltose. 
Glycerol, xylose, lactose, sucrose, mannitol 
and salicin not fermented. 

Starch is hydrolyzed. 

Non-lipolytic. 

Nitrites not produced from nitrates. 

Ammonia produced from peptone but not 
from urea. 

Casein not digested. 

Aerobic, facultative. 

Optimum temperature, between 20° and 
25° C. 

Source: Isolated from sea water. 

Habitat: Common; probably widely dis- 
tributed. 

9. Vibrio phytoplanktis ZoBell and 
Upham, 1944. (Bull. Scripps Inst, of Ocean- 
ography, Univ. Calif., 5, 1944, 261.) 

phy.to.plank'tis. Gr. neut.n. phylum 
plant; Gr. adj. plancius wandering; M.L. 
neut.n. plankton (plancium) plankton; M.L. 
neut.n. phytoplankton plant plankton; M.L. 
adj. ^phytoplanktis of the phytoplankton. 

Curved rods, 0.5 to 0.6 by 2.0 to 5.4 mi- 
crons, occurring mostly singly with some 
short spiral chains. Bipolar staining. Motile 
by means of a single polar flagcllum. Gram- 
negative. 

Note: All differential media except the 



236 



ORDER I. PSEUDOMONADALES 



fresh-water broth, litmus milk and potato 
were prepared with sea water. 

Gelatin colonies: Diffuse, irregular; waxy 
appearance, slightly depressed; rapid lique- 
faction. 

Gelatin stab: Slow, crateriform, lique- 
faction becoming stratiform. Buff pigment. 

Agar colonies: 1 to 2 mm in diameter, 
translucent, smooth, convex, circular. 

Agar slant: Luxuriant, echinulate; water.y 
appearance; slightly mucoid, glistening 
growth with buff or cream pigment. 

Sea-water broth: Heavy turbidity; abun- 
dant, flocculent sediment; surface ring. 

Fresh-water broth: No visible growth. 

Litmus milk: No visible change. 

Potato: No visible growth. 

Indole not produced. 

Hydrogen sulfide is produced. 

Acid but no gas from glucose, maltose 
and sucrose. Glycerol, xylose, lactose, man- 
nitol and salicin not fermented. 

Starch not hydrolj^zed. 

Non-lipolytic. 

Nitrites not produced from nitrates. 

Ammonia produced from peptone but 
not from urea. 

Casein is digested. 

Aerobic, facultative (good anaerobic 
growth). 

Optimum temperature, between 20° and 
25° C. 

Source: Lsolated from sea water and ma- 
rine phytoplankton. 

Habitat: Presumably widely distributed. 

10. Vibrio costicolus Smith, 1938. (Roy. 
Soc. Queensland, Proc. for 1937, 49, 1938, 

29.) 

cos.ti'co.lus. L. noun, cos/o rib; L. v. colo 
to dwell; M.L. adj. costicolus rib dwelling 
(from bacon). 

Curved rods, 0.5 by 2.0 to 4.0 microns; 
old cells coccoid. Actively motile by means 
of a single, polar flagellum. Young cultures 
show pronounced beaded staining. Gram- 
negative. 

No growth on media which does not con- 
tain salt. Limit for growth, 2 to 23 per cent 
NaCl; optimum, 6 to 12 per cent. 



Gelatin stab: No liquefaction. However, 
some strains liquefy within 2 days at 32° C; 
these may represent a distinct variety or a 
separate species. 

Agar colonies: Circular, entire, convex, 
glistening, non-viscid. 

Agar slant: Abundant, filiform, trans- 
parent or translucent growth. 

Broth : Pellicle formation varies from 
absent to pronounced, whitish and non- 
coherent. 

Litmus milk: Not coagulated. 

Potato: Sparse, moist, brownish growth. 

Indole not produced. 

Hj^drogen sulfide produced. 

Acid from glucose, fructose, sucrose, man- 
nose, mannitol and glycerol. No acid from 
galactose, lactose, maltose, rhamnose, raf- 
finose, arabinose, xylose, sorbitol, dextrin, 
starch or salicin. 

Acetjdmethylcarbinol not produced. 

Non-lipolytic. 

Nitrites produced from nitrates. 

Catalase-positive. 

Aerobic, facultative. 

Optimum temperature, between 30° and 
35° C; temperature range, 2° to 42° C. 

Related organisms: Robinson (A Possible 
Explanation of Microbial Halophilism, The- 
sis, McGill University, 1950, 92 pp.) isolated 
a similar organism from bacon-curing brines 
in Canada. At concentrations of 11.7 and 
17.5 per cent NaCl, cells are spirillum- 
shaped and sluggishly motile. Pellicle formed 
on broth. Gelatin liquefied. Acetjdmeth- 
ylcarbinol produced. Catalase and urease 
absent. Acid from raffinose and inulin. No 
acid from mannose, dulcitol, cellobiose, 
adonitol or ethyl alcohol. Organism will 
note grow in absence of salts, but NaCl may 
be replaced by KCl, NaBr, NaoS.Oa , LiCl 
or MgCU (also see Flannery, Doetsch and 
Hansen, Jour. Bact., 64, 1952, 713-17). 

Source: Isolated from the tainted ribs 
of bacon and tank brines in bacon factories 
in Australia. 

Habitat: Found in cured meats and meat- 
curing brines. 

11. Vibrio halonitrificans* Smith, 1938. 



* This organism is, in realitj-, a denitrifier, 
inappropriate. 



not a nitrifier, and therefore this name 



FAMILY VII. SPIRILLACEAE 



237 



(Roy. Soc. Queensland, Proc. for 1937, 49, 
1938, 29.) 

ha.lo.ni.tri'fi.cans. Gr. noun hals , hairs 
the sea salt; M.L. part. adj. nitrificans ni- 
trifying; M.L. adj. halonitrificans nitrifying 
salt. 

Curved rods, usually 0.3 by 1.2 to 2.5 mi- 
crons, occurring singly. Motile by means of 
a single, polar flagellum. No marked varia- 
tion in form in media of varied salinity. 
Stain somewhat faintly with the usual 
stains. Gram-negative. 

No growth on media which does not con- 
tain salt. Limit for growth, 1 to 23 per cent 
salt; optimum growth in 4.0 to 6.0 per cent 
salt. 

Gelatin stab: Liquefied within 7 days at 
35° C.; at 20° C. shallow, superficial lique- 
faction was evident in 20 days. 

Agar colonies: Light amber, glistening, 
convex, transparent, non-viscid, slightly 
spreading. 

Agar slants: Growth slow at 4° C., col- 
onies appearing in 14 days. 

Nutrient and nitrate broths: Growth. 
No growth, however, when covered with a 
paraffin oil seal. 

Litmus milk: Not coagulated; growth 
slight or absent. 

Potato: Growth moist, fairly abundant, 
whitish. 

Indole not produced. 

Hydrogen sulfide not produced. 

Glucose, fructose, sucrose, mannose, 
rhamnose, galactose, lactose, maltose, raf- 
finose, sorbitol and glycerol not fermented. 

Acetylmethylcarbinol not produced. 

Non-lipolytic. 

Nitrites produced from nitrates. 

Catalase-negative. 

Aerobic. 

Temperature relations: Optimum, be- 
tween 30° and 35° C. Slow growth at 4° C. 
Killed in 10 minutes in 6 per cent saline 
broth at 55° C. 

Limiting reactions for growth, pH 5.4 
and pH 9.2. 

Not pathogenic for guinea pigs or mice. 

Source: Five strains were isolated from 
tank brines from bacon-curing factories 
in Australia. The strains showed little var- 
iation in characters. Except for its ability 
to liquefy gelatin, this species resembles 



the organisms isolated by Sturges and 
Heideman (Absts. Bact., 7, 1923, 11; ibid., 
8, 1924, 14; ibid., 9, 1925, 2) in the U. S. A. 
Habitat: Known to be found in meat- 
curing brines but probably more widely 
distributed. 

12. Vibrio luminosus Beijerinck, 1888. 
(Vibrio luminosus (nomen nudtim) Beije- 
rinck, Botan. Zeitg., 46, 1888, 763; Photo- 
bacterium luminosum Beijerinck, Arch. 
N^erl. d. Sci. Exact, et Natur., 23, 1889, 401 ; 
Microspira luminosa Migula, Syst. d. Bakt., 
2, 1900, 1015.) 

lu.mi.no'sus. L. adj. luminosus Inminons. 

Small rods having the size and form of the 
cholera vibrio when grown in media con- 
taining little nitrogen and carbohydrates. 
Sometimes form chains of vibrios which 
resemble spirilla. In richer media the cells 
become much larger. Motile. Gram-nega- 
tive (Chester, 1897). 

Gelatin: Liquefied. In presence of 0.5 per 
cent asparagine and 0.5 per cent peptone, 
offensive odors not produced. Putrefaction 
of the gelatin occurs when the nitrogen 
source is insufficient. 

Peptonized meat bouillon gelatin: No 
growth. Good growth and luminescence 
with the addition of 3.0 to 3.5 per cent of 
sea salt, potassium chloride or magnesium 
chloride. 

Agar: Growth rapid, shines feebly. 

Sea-water broth: Produces forms which 
resemble the bacteroids of legume bacteria. 

Blood serum: No growth. Addition of 3.0 
to 3.5 per cent of sea salt, potassium chloride 
or magnesium chloride allows good growth 
and luminescence. 

Nitrates not reduced. 

Indigo-blue not readily reduced. 

Salt tolerance: In order to assure phos- 
phorescence and good growth, the osmotic 
tension of inorganic salt solutions used for 
cultivation should be equivalent to that 
produced in a 3 per cent sodium chloride 
solution. 

Optimum temperature for growth and 
luminescence, between 25° and 28° C. 

Aerobic. 

Quality of luminescence: Bluish green, 
persisting for 1 to 2 weeks. 

Distinctive characters: Develops only 



238 



ORDER I. PSEUDOMONADALES 



on neutral or f eebl}'^ alkaline media : a slight 
quantity of acid completely prevents growth 
and the production of luminescence. Lu- 
minescence occurs on organic matter only 
when a sufficient proportion of inorganic 
salt is present. 

Source: Isolated in Holland from coastal 
sea water, dead sea fish and Crustacea. 

Habitat: Found in coastal sea water, on 
dead fish, Crustacea and other salt-water 
animals, on meat and even on soldiers' 
wounds where they produce no known harm- 
ful effects. No food poisoning has ever been 
traced to meat on which these organisms 
have grown (Niven, Circular No. 2, Amer- 
ican Meat Inst. Foundation, 1951, 1-11). 

13. Vibrio indicus (Beijerinck, 1889) 
Lehmann and Neumann, 1896. (Bacillus 
phosphorescens Fischer, Ztschr. f. Hyg., S, 
1887, 58; also see Anonymous, Sitzber. d. 
Gesell. naturf. Freunde zu Berlin, 1886, 
162; Photobacterium indicum Beijerinck, 
Arch. Need. d. Sci. Exact, et Natur., 23, 
1889, 401; not Photobacterium phosphores- 
cens Beijerinck, loc. cit.; Lehmann and 
Neumann, Bakt. Diag., 1 Aufl., 2, 1896, 
341; Pseudomonas phosphorescens Bergej' 
et al.. Manual, 3rd ed., 1930, 177.) 

in'di.cus. L. adj. indicus of India. 

Description taken from Fischer (op. cit., 
1887, 58) and Beijerinck (op. cit., 1889, 401). 

Small, thick rods 2 to 3 times as long as 
wide with rounded ends; occasionally spiral 
and short, irregularly-curved filamentous 
forms are found. Motile. Stain lightly with 
aniline dyes. Gram-negative (Chester, 1897). 

Gelatin colonies: After 36 hours, small, 
circular, grayish white, punctiform. Lique- 
faction, forming a slightly concave surface. 

Blood serum: Grayish white, slimy 
growth. 

Potato: Thin, white laj'er in 2 to 3 days. 

Cooked fish: Abundant growth. Entire 
surface covered with a grayish white, slimy 
growth. Bluish white phosphorescence. 

Alkaline broth: Slight turbidity in 24 
hours. Pellicle in 3 days. 

Acid broth: No turbidity. No phospho- 
rescence. 

Milk: No growth. 

No gas produced. 



Nitrates not reduced. 

Indigo-blue not readily reduced. 

Not pathogenic for laboratory animals. 

Salt tolerance: To assure phosphorescence 
and good growth, the osmotic tension of 
inorganic salt solutions used for cultivation 
should be equivalent to that produced in a 
3 per cent sodium chloride solution. 

Optimum temperature for growth and 
luminescence, between 30° and 32° C. Min- 
imum, 15° C. 

Aerobic. 

Quality of luminescence: Bluish to green, 
persisting for 1 to 2 weeks. 

Distinctive character: Luminescence on 
organic matter occurs only when a sufficient 
proportion of inorganic salt is present. 

Source: Isolated from sea water of the 
West Indies. 

Habitat: Found in coastal sea water and 
on dead fish, Crustacea and other salt-water 
animals; they are also found on meat and 
even on soldiers' wounds where they pro- 
duce no known harmful effects. No food 
poisoning has been traced to meat on which 
these organisms have grown (Niven, Cir- 
cular No. 2, American Meat Inst. Founda- 
tion, 1951, 1-11). 

14. Vibrio albensis Lehmann and Neu- 
mann, 1896. (Elbe vibrio, Dunbar, Deutsche 
med. Wochnschr., 19, 1893, 799; Lehmann 
and Neumann, Bakt. Diag., 1 Aufl., 2, 1896, 
340; Microspira dunbari Migula, Syst. d. 
Bakt., 2, 1900, 1013.) 

al.ben'sis. M.L. adj. aZftensj's pertaining 
to the (river) Elbe. 

Early descriptions merel.y report this 
organism as morphologically and culturally 
(except for phosphorescence and patho- 
genicity) indistinguishable from Vibrio 
comma. Some of the early workers even 
failed to observe phosphorescence. Descrip- 
tion taken from Gorham (in Dahlgren, Jour. 
Franklin Inst., 180, 1915, table following 
714) and Warren (Jour. Bact., 49, 1945, 
549); also see Sonnenschein (Cent. f. Bakt., 
I Abt., Orig., 123, 1931, 92). 

Curved rods, 1.2 by 2.1 microns, occurring 
singly and in pairs. Motile b}^ means of a 
single, polar flagellum. Not encapsulated. 
Gram-negative. 



FAMILY VII. SPIRILLACEAE 



239 



Gelatin colonies: Small, j^ellowish white. 

Gelatin stab: Liquefaction. Growth at 
the surface and along the stab. 

Agar: Abundant growth. 

Agar slant: Growth dull and wrinkled. 

Blood agar: Good growth and lumines- 
cence; beta hemolysis. 

Broth: Pellicle formed. 

Koser's citrate medium: Growth and lu- 
minescence. 

Milk: Growth. 

Potato: Luxuriant growth. 

Indole produced. 

Hydrogen sulfide not produced. 

Acid but no gas from glucose and sucrose. 
No acid or gas from lactose. 

Starch hydrolyzed. 

Gives a cholera-red reaction, i.e., pro- 
duces both indole and nitrites. 

Nitrites produced from nitrates. 

Optimum salt concentration, 0.9 per cent. 

Temperature relations: Optimum, 22° C.; 
growth at 37.5° C. 

Aerobic, facultative. 

Distinctive characters: Morphologically 
and culturally like Vibrio comma. Lumi- 
nescent. Pathogenic to guinea pigs and 
pigeons. 

Source: Originally isolated from the Elbe 
River. If Vibrio phosphorescens Jermoljewa 
(Cent. f. Bakt., I Abt., Orig., 100, 1926, 
170) is accepted as identical with this spe- 
cies, then it has also been found in the in- 
testinal contents of three cholera patients, 
one gastroenteritis and one typhoid pa- 
tient; Jermoljewa (ibid., 171) also isolated 
his organism from the bile of a cadaver. 
Sonnenschein (op. cit., 12S, 1931, 92) reiso- 
lated this species from a fish taken from 
the Elbe River and found that it main- 
tained its ability to luminesce when grown 
in o.x bile. 

Habitat: Found in fresh water, in human 
feces and in bile. Probably widely distrib- 
uted. 

15. Vibrio pierantonii (Zirpolo, 1918) 
Meissner, 1926. (Bacillus pierantonii Zir- 
polo. Boll. Soc. Nat. Napoli, 30, (1917) 
1918, 206; Meissner, Cent. f. Bakt., II Abt., 
67, 1926, 200.) 

pier.an.to'ni.i. M.L. gen. noun pierantonii 



of Pierantoni; named for Prof. U. Pieran- 
toni, an Italian scientist. 

Rods, 0.5 by 1.5 microns, with rounded 
ends. Rods curved and vibrio-shaped ac- 
cording to Meissner (ibid., 201). Motile by 
means of one to three polar flagella. Gram- 
negative. 

Gelatin colonies: Circular and irregularly 
lobulate. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular, light green, 
smooth, entire. 

Glycerol agar slant: Slightly luminous 
streak. 

Broth: Turljid, with pellicle. 

Indole not produced. 

Acid from glucose and maltose. Some 
strains also attack lactose, sucrose and 
mannitol. 

Best growth in alkaline media. 

Aerobic, facultative. 

Optimum temperature, 37° C. 

Source: Isolated from the photogenic 
organ of the cephalopod Sepiola intermedia 
Naef. 

16. Vibrio agarliqiiefaciens (Gray and 
Chalmers, 1924) Bergey et al., 1934. (Mi- 
crospira agar-liquefaciens (sic) Gray and 
Chalmers, Ann. Appl. Biol., 11, 1924, 325; 
Bergey et al., Manual, 4th ed., 1934, 119.) 

a.gar.li.que.fac'i.ens. Malay agar, a jelly 
from seaweeds; L. v. liquefacio to liquefy; 
M.L. part. adj. agarliquefaciens liquefying 
agar. 

Short, curved rods, usually c-shaped, 
with occasional s-shaped and coccoid forms. 
Cells 2.0 microns long by 0.5 to 0.7 micron 
broad; 3.0 to 5.0 microns long in division 
stages. Coccoid forms stained, 0.5 to 0.7 
micron long. Motile by means of a single, 
polar flagellum. Gram stain not reported. 

Gelatin stab: Very slight surface growth 
after one month; the streak then shows a 
beaded line. No liquefaction. 

Agar colonies: Surface colonies appear 
as a whitish growth in a depression, sur- 
rounded by a white ring. The colony is later 
surrounded by a ring of liquid agar. Deep 
colonies show a clear area and may be irreg- 
ular, oval or angular. 

Agar slant: A deep groove is cut along 



240 



ORDER I. PSEUDOMONADALES 



the inoculation streak, whitish growth along 
sides. The gel is later much weakened. 

Broth: Slightly turbid. No pellicle. 

Acid from glucose, lactose and maltose. 
No acid from sucrose or glycerol. 

Starch hydrolyzed. 

Decomposes cellulose and agar. The pres- 
ence of one per cent glucose prevents the 
liquefaction of agar. 

Nitrites produced from nitrates. 

Utilizes ammonium salts as a source of 
nitrogen. 

Aerobic. 

Temperature relations: Optimum, 25° C; 
will grow at 16° but not at 34° C. 

Habitat: Soil. 

17. Vibrio andoii Aoi and Orikura, 1928. 
(Eine neue Agarzersetzende Bodenbak- 
terienart, Aoi, Cent. f. Bakt., II Abt., 63, 
1924, 30; Aoi and Orikura, Cent. f. Bakt., 
II Abt., 74, 1928, 331.) 

an.do'i.i. M.L. gen .no\in andoii of Andoi; 
named for Andoi, a Japanese scientist. 

Curved rods with more or less tapering 
ends, c- or s-shaped, 0.5 to 0.8 by 1.5 to 2.5 
microns. Motile by means of a single, polar 
flagellum. Gram-negative. 

Gelatin: No growth. 

Peptone agar media: No growth. 

Peptone broth: No growth. 

Litmus milk: No growth. 

Potato: No growth. 

Ammonium sulfate agar colonies: Puncti- 
form, circular, concave, surrounded with 
a clear zone. 

Ammonium sulfate agar slant: Growth 
grayish, becoming straw-yellow, sinking 
into the medium as the agar liquefies. 

Glucose, fructose, galactose, mannose, 
xylose and "konjac" assimilated. Konjac, 
a Japanese food in tablets and strips, re- 
sembles gelatinized agar; it is prepared from 
the tuber of the konjac plant, Amor-pho- 
phallus rivieri. 

Starch hydrolyzed. 

Cellulose and lignin not attacked. 

Xylan decomposed. 

Cellobiose decomposed. 

Aerobic, facultative. 

Temperature relations: Optimum, be- 
tween 25° and 28° C. Minimum, 8° C. Max- 
imum, 37° C. 



Optimum pH, between 6.8 and 7.5. 

Distinctive characters : When grown sym- 
biotically with a second, unnamed species 
found in rotted manure, the latter species 
is able to hydrolyze cellulose in straw, prob- 
ably because the first species (Vibrio andoii) 
decomposes the xylan that protects the 
cellulose from the action of the second spe- 
cies. 

Source: Isolated from rotted stable ma- 
nure. 

Habitat: Presumably decomposing or- 
ganic matter. 

18. Vibrio beijerinckii Stanier, 1941. 
(Tyrosine vibrio of the sea, Beijerinck, Proc. 
Sect. Sci., Kon. Akad. Vetenschappen, 
Amsterdam, 13, 1911, 1072; Stanier, Jour. 
Bact., 42, 1941, 539.) 

beij .er.inck'i.i.M.L. gen. nounbeijerinckii 
of Beijerinck; named for Prof. M. W. Beije- 
rinck, the Dutch biologist who first dis- 
covered this species. 

Small, curved rods, 0.4 to 1.0 by 2.0 to 
6.0 microns, usually single, sometimes oc- 
curring in short chains; in older cultures, 
occur mostly as straight rods. Actively 
motile by means of polar flagella. Encap- 
sulated. Gram-negative. 

Sea-water peptone agar colonies : Round, 
smooth, glistening, mucoid, entire. White 
to gray in color. After 24 hrs, 3 to 4 mm in 
diameter. The agar softens and clears for 
a distance of 3 to 5 mm from the edge of the 
colony, the outer edge of the gelase field 
being sharply defined. The colonies eventu- 
ally grow to as much as 10 mm in diameter 
with a gelase margin of 2 to 3 cm. 

Sea-water nitrate agar: Growth is slower 
than with peptone, but pigment production 
is much more marked. After 48 hours, col- 
onies are 1 mm in diameter with a dark 
brown to black center and a colorless mar- 
gin. Pigmented granules may be seen lying 
among the cells. 

Sea-water peptone agar slant: Abundant 
growth after 24 hours, spreading, slightly 
raised, smooth, glistening, mucoid, dirty- 
white to dark gray in color. Agar digestion 
is evidenced onlj' by a general softening of 
the slant. After several days, a pale brown, 
diffusible pigment is produced by some 
strains. 



FAMILY VII. SPIRILLACEAE 



241 



Sea-water nutrient gelatin slant: Good, 
filiform, gray growth after 24 hours, with 
considerable liquefaction. Slant completely 
liquefied after one week. 

Sea-water nutrient gelatin stab: Fair, 
filiform growth after 24 hours, best at sur- 
face. Napiform liquefaction, complete after 
7 to 10 days. 

Sea-water peptone broth: Heavily turbid 
after 24 hours. Gray pellicle and flocculent; 
gray sediment. Later a light brown, soluble 
pigment is formed. 

Indole not produced. 

Hydrogen sulfide not produced. 

Very slight or no acid from glucose, ga- 
lactose, maltose, lactose and cellobiose. 
Arabinose, xylose and sucrose not fer- 
mented. Agar is extensively softened but 
not liquefied. Cellulose, chitin and alginic 
acid not attacked. 

Starch is rapidly hydrolyzed. 

Nitrites produced from nitrates. 

Ammonia and nitrates utilized as sole 
sources of nitrogen. 

Urease-negative. 

Catalase-positive. 

Aerobic. 

Optimum temperature, 23° C.; grows 
between 5° and 30° C. 

Salt range: 0.25 to 6.0 per cent. Optimum, 
between 2.0 and 4.0 per cent. 

Source: Found in sea-water and, in the 
winter months, in the plankton; also found 
in fresh water and in sewage. Isolated both 
in Holland and in California. Along the 
coast of California it appears to be the most 
common species of marine agar-digester. 

Habitat: Widely distributed in sea water 
and also in fresh water. 

19. Vibrio fuscus Stanier, 1941. (Jour. 
Bact., 4^, 1941,540.) 

fus'cus. L. adj. fiiscus dark or tawny. 

Small, slightly curved rods, 0.7 by 1.5 to 
5.0 microns, usually occurring singly, some- 
times in short chains. Very actively motile 
by means of a single, polar flagellum. Not 
encapsulated. Gram-negative. 

Sea-water peptone agar colonies: 1 mm 
in diameter after 48 hours; round, smooth, 
glistening, translucent, entire, pale ^yellow 
and slightly sunken in the agar. Colonies 
several mm in diameter after 7 days, be- 



coming bright yellow, then pale brown. 
They are sharply sunken into the agar and 
are surrounded b}' a narrow, sharply de- 
fined gelase field. Liquefaction does not 
occur except on heavily seeded plates. 

Sea-water peptone agar slant : Fair growth 
after 48 hours, filiform, smooth, glistening, 
translucent, pale yellow, slightly sunken 
in the agar. Later a pale yellow, diffusible 
pigment may be produced, and the streak 
tends to become light brown in color. On 
old slants the agar is slightly liquefied. 

Sea-water nutrient gelatin slant: Fili- 
form, smooth, pale j-ellow growth after 48 
hours with slight liquefaction; liquefaction 
almost complete after 7 days. 

Sea-water gelatin stab: Filiform growth 
after 48 hours with slight liquefaction; col- 
orless; growth best at surface. Later the 
liquefaction becomes stratiform and almost 
complete. 

Sea-water peptone broth: Good growth 
after 48 hours; turbid with a granular sedi- 
ment and yellow pellicle. 

Indole not produced. 

Hydrogen sulfide not produced. 

Glucose, galactose, sucrose, maltose, 
lactose, xylose and cellobiose attacked. 
Arabinose not utilized. Cellulose is attacked 
to a slight extent, and agar is softened and 
sometimes liquefied. Chitin and alginic acid 
are not attacked. 

Starch not hydrolyzed. 

Nitrites produced from nitrates. 

Urease-negative. 

Catalase-positive. 

Aerobic. 

Optimum temperature, between 20° and 
25° C. Grows between 5° and 30° C. 

Salt range, 1.0 to 5.0 per cent. Optimum, 
between 2.0 and 4.0 per cent. 

Source: Found only once in a marine cel- 
lulose-enrichment culture in California. 

Habitat: Presumably salt water. 

20. Vibrio granii (Lundestad, 1928) 
Stanier, 1941. (Bacterium granii Lundestad, 
Cent. f. Bakt., II Abt., 75, 1928, 330; Stan- 
ier, Jour. Bact., 42, 1941, 538.) 

gra'ni.i. M.L. gen. noun granii of Gran; 
named for Prof. H. H. Gran, who first de- 
tected agar-liquef3'ing bacteria. 

Rods, 0.6 to 0.8 by 1.4 to 2.4 microns, with 



242 



ORDER I. PSEUDOMONADALES 



rounded ends, occurring singly, in pairs, 
and at times in short chains. Motile. Polar 
flagellate (Stanier, loc. cit.). Gram-negative. 

Fish-gelatin colonies: Punctiform, black, 
glistening. 

Fish-gelatin stab: Slow, crateriform lique- 
faction. 

Sea-weed agar colonies: Circular, flat, 
opaque, glistening, white, slimy, entire. 
Agar is dissolved. 

Fish-agar slant: Flat, white, elevated, 
glistening, undulate growth. Liquefaction. 

Broth: Turbid with grayish white, slimy 
sediment. 

Indole not produced. 

No action on sugars. 

Starch usuallj^ hydrolyzed. 

Nitrites not produced from nitrates. 

Aerobic, facultative. 

Optimum temperature, between 20° and 
25° C. Minimum, between 0° and 5° C. Max- 
imum, between 30° and 32° C. 

Source: Isolated from sea-water of the 
Norwegian Coast. 

Habitat: Presumably found in sea water 
and on sea weeds. 



22. Vibrio cyclosites Gray and Thorn- 
ton, 1928. (Cent. f. Bakt., II Abt., 73, 1928, 
92.) 

cyc.lo.si'tes. Gr. nonn ajclus a ring: Gr. 
V. sited to eat; M.L. adj. cyclosites feeding 
on rings, i.e., on ring compounds. 

Curved rods 0.5 to 1.0 by 1.5 to 4.0 mi- 
crons. Motile by means of a single, polar 
flagellum. Gram-negative. 

Gelatin colonies: Circular, buff to brown, 
flat, smooth, glistening, entire. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular to irregular, pale 
buff (later greenish), smooth, entire. 

Agar stab: Filiform, greenish buff, raised, 
smooth, undulate. 

Broth: Turbid. 

Indole not reported. 

Acid from glucose. 

Starch not hydrolj'zed. 

Nitrites not produced from nitrates. 

Attacks phenol and ?«-cresol. 

Aerobic, facultative. 

Optimum temperature, between 30° and 
35° C. 

Habitat: Soil. 



21. Vibrio neocistes Gray and Thorn- 
ton, 1928. (Cent. f. Bakt., II Abt., 73, 1928, 
92.) 

ne.o.cis'tes. Gr. adj. nensnev;; Gr. noun 
ciste box; M.L. fern. gen. n. neocistes of New- 
ark, a city. 

Curved rods 0.5 to 1.0 by 1.0 to 4.0 mi- 
crons. Motile by means of one to three polar 
flagella. Gram stain not recorded. 

Gelatin colonies: Liquefied. 

Gelatin stab: Liquefied. Medium red- 
dened. 

Agar colonies: Circular or amoeboid, buff 
to brownish, convex, smooth, glistening, 
entire. 

Agar slant: Filiform, fluorescent, raised, 
smooth, glistening, undulate. 

Broth: Turbid. 

Acid from glucose. 

Starch not hydrolyzed. 

Nitrites not produced from nitrates. 

Attacks naphthalene. 

Aerobic, facultative. 

(Optimum temperature, between 30° and 
35° C. 

Habitat: Soil. 



23. Vibrio oxaliticus Bhat and Barker, 
1948. (Jour. Bact., 55, 1948, 359.) 

ox.a.li'ti .cus. Gr. noun oxalis sorrel, a 
sour plant; Gr. adj. lyticus dissolving; M.L. 
adj. oxaliticus intended to mean decom- 
posing oxalate. 

Curved rods 0.4 by 1.3 microns. Actively 
motile by means of a single, polar flagellum. 
Not encapsulated. Gram-negative. 

Nutrient agar colonies: Small, moist, 
raised, entire; no chromogenesis. Pin-point 
in size in 48 hours, growing slowly until 
they reach a diameter of 1.5 mm in 6 days. 

Nutrient broth: Moderate growth after 
24 hours, appearing at first as a thin film 
while a slight, general turbidity develops 
in another 24 to 48 hours. 

Calcium oxalate agar: Growth rapid and 
colonies small; medium becomes alkaline. 

Oxalate broth: Becomes turbid following 
the formation of a slight surface film. 

Oxalates and pyruvates support growth 
within 3 to 4 days when added to a mineral 
medium as the sole carbon source; formates 
support growth only when the incubation 
period is extended. The following do not 



FAMILY VII. SPIRILLACEAE 



243 



support growth under any of the above 
conditions when added to the mineral me- 
dium: butyrates, citrates, lactates, malates, 
malonates, succinates, tartrates or glucose. 

Indole not produced. 

Hydrogen sulfide not produced. 

Nitrites not produced from nitrates. 

Aerobic. 

Source: Five strains were isolated from 
Boston, Mass., and Berkeley, California, 
soils by inoculation of soil into a medium 
containing potassium oxalate and other 
minerals in distilled water. All soil samples 
tested showed the presence of this species. 
Ayers, Rupp and Johnson (U. S. Dept. Agr. 
Bull. No. 782, 1919, 38 pp.) and den Dooren 
de Jong (Dissertation, Delft, 1926, Table 
XVIII) tested over 125 strains of bacteria 
without finding any that decomposed ox- 
alate. Bassilik (Jahrb. wiss. Bot., 63, 1913, 
255) found only three strains out of 90 tested 
which decomposed oxalate, two slowly; 
the third was the species described by him 
(Vibrio extorquens). 

Habitat: Widely distributed in soil. 

24. Vibrio extorquens (Bassalik, 1913) 
Bhat and Barker, 1948. (Bacilhis extorquens 
Bassalik, Jahrb. f. wiss. Bot., 53, 1913, 255; 
Bhat and Barker, Jour. Bact., 55, 1948, 367; 
Pseudomonas extorquens Janota, Med. Dos- 
wiadczalna i Mikrobiol., 2, 1950, 131; see 
Biol. Abstracts, .25,1951, Abs. no. 34148.) 

ex.tor'quens. L. puTt.ad] . extorquens twist- 
ing out. 

Slightly curved rods, 1.5 by 3.0 microns. 
Motile by means of a single, polar flagel- 
lum. Gram-negative. 

Gelatin media: Poor growth. Colonies 
small (less than 1 mm in diameter in 7 days), 
round, entire, butyrous. Surface colonies 
dirty yellow to yellowish red, eventually 
becoming a beautiful red color. No lique- 
faction. 

Oxalate and similar mineral media: 
Growth rapid and abundant. 

Peptone-agar colonies: Growth slower 
than on gelatin. 

Liquid oxalate media. Grows rapidly as 
a rose-colored film on the bottom and walls 
of the flask, leaving the liquid clear. 

Potato: Slow growth with darkening of 
potato. 



Litmus milk: Not coagulated. Reaction 
becomes alkaline but growth is poor. 

Aerobic, facultative. 

Optimum temperature, between 25° and 
30° C. Poor growth at 37° C. 

Optimum pH : Prefers media with an alka- 
line reaction. 

Distinctive characters: In old cultures in 
liquid calcium oxalate media and especially 
in media made with plant materials con- 
taining oxalate crystals, the cells become 
encrusted with a surface deposit. This ap- 
pears to be calcium carbonate and is easily 
dissolved with dilute acid, especially dilute 
HCl. 

Source: Originally isolated by adding the 
e.xcreta of earthworms that had ingested 
plant materials containing oxalate crystals 
to a liquid medium containing ammonium 
oxalate. Pure cultures were isolated with 
difficulty by using a silica gel medium con- 
taining ammonium oxalate. Later these 
organisms were found to be generally pres- 
ent in forest and garden soils in Switzerland. 

Habitat: Presumably widely distributed 
in soil. 

25. Vibrio cuneatus Gray and Thornton, 
1928. (Cent. f. Bakt., II Abt., 73, 1928, 92.) 

cu.ne.a'tus. L. part. adj. amea/z/s wedge- 
shaped. 

Curved rods, 1.0 by 1.0 to 3.0 microns, 
the cells tapering at one extremity. Motile 
by means of one to five polar flagella. Gram- 
negative. 

Gelatin colonies: Liquefied. 

Gelatin stab: Liquefied. 

Agar colonies: Circular to amoeboid, 
white to buff, flat to convex, smooth, trans- 
lucent, border entire. 

Agar slant: Filiform, whitish, smooth, 
glistening. 

Indole production not recorded. 

No acid from carbohydrate media. 

Starch not hydrolyzed. 

Nitrites not produced from nitrates. 

Attacks naphthalene. 

Aerobic, facultative. 

Optimum temperature, between 30° and 
35° C. 

Source: One strain was isolated from 
soil from Rothamsted, England. 

Habitat: Soil. 



244 



ORDER I. PSEUDOMONADALES 



26. Vibrio percolans Mudd and Warren, 
1923. (Jour. Bact., 8, 1923, 447.) 

per'co.lans. L. v. percolo to filter through; 
L. part. adj. percolans filtering through. 

Curved rods, 0.3 to 0.4 by 1.5 to 1.8 mi- 
crons, occurring singly or in short chains. 
Pleomorphic. Actively motile by means of 
1 to 3 polar flagella. Gram-negative. 

Gelatin stab: No liquefaction. 

Agar colonies: Circular, slightly convex, 
amorphous, entire. 

Agar slant: Bluish white, glistening 
streak. 

Broth: Turbid. Pellicle, sediment. 

Litmus milk: Unchanged. 

Potato: White, slimy streak. 

Coagulated blood serum not liquefied. 

Indole not produced. 

No action on carbohydrates. 

Starch not hydrolyzed. 

Nitrites not produced from nitrates. 

Passes through bacterial filters (Berkefeld 
V candles). 

Aerobic, facultative. 

Optimum temperature, 30° C. 

Non-pathogenic. 

Relationships to other species: Except 
for polar flagellation, this species has char- 
acters much like those of Alcaligenes faecalis 
Castellani and Chalmers. The two species 
are frequently confused. For example Leh- 
mann and Neumann renamed Alcaligenes 
faecalis as Vibrio alcaligenes in their Bakt. 
Diag., 7 Aufl., 2, 1927, 548, in the mistaken 
idea that the former organism is polar flagel- 
late. Leifson and Hugh (personal com- 
munication, 1954), who recognize the spe- 
cies Vibrio alcaligenes, report that Vibrio 
alcaligenes produces nitrites from nitrates 
and that it does not hydrolyze urea (with 
possible rare exceptions). They report also 
that Vibrio alcaligenes occurs more fre- 
quently in the intestine than does Alca- 
ligenes faecalis Petruschky. 

Source: Isolated from a hay infusion. 

Habitat: Water. 

27. Vibrio adaptatiis ZoBell and Up- 

ham, 1944. (Bull. Scripps Inst, of Ocean- 
ography, Univ. Calif., 6, 1944, 258.) 

a.dap.ta'tus. L. part. adj. adaptatus fitted, 
adapted. 

Curved rods, 0.4 to 0.5 by 1.6 to 2.3 mi- 



crons, only slightly curved, occurring singly 
and sometimes in pairs. Motile by means 
of a single, polar flagellum. Gram-negative. 

Note: All differential media except the 
fresh-water broth, litmus milk and potato 
were prepared with sea water. 

Gelatin colonies: Pin-point, yellow. 

Gelatin stab: No liquefaction. Yellow, 
filiform growth along stab. 

Agar colonies: Punctiform, yellow, 
opaque, pulvinate, smooth. 

Agar slant: Luxuriant, filiform, shiny 
growth with waxy yellow pigment. 

Sea-water broth: Moderate turbidity; 
thick, yellow pellicle; slight, flocculent 
sediment. 

Fresh-water broth: Moderate growth. 

Litmus milk: No visible change. 

Potato : No visible growth. 

Indole not produced. 

Hydrogen sulfide not produced. 

Glucose, sucrose, maltose, lactose, xylose, 
glycerol, mannitol and salicin not fer- 
mented. 

Starch not hydrolyzed. 

Non-lipolytic. 

Nitrites not produced from nitrates. 

Ammonia produced from peptone but 
not from urea. 

Casein not digested. 

Aerobic, facultative (poor anaerobic 
growth) . 

Optimum temperature, between 20° and 
25° C. 

Source: Isolated from sea water and from 
marine sediments. 

Habitat: Common; probably widely dis- 
tributed. 

28. Vibrio piscium David, 1927. (Cent, 
f. Bakt., I Abt., Orig., 102, 1927, 46.) 

pis'ci.um. L. noun piscis a fish; L. gen.pl. 
piscium of fishes. 

Curved rods 0.3 to 0.5 by 2.0 microns. 
Motile by means of a single, polar flagellum. 
Gram-negative. 

Gelatin colonies: Circular, granular, 
opaque. 

Gelatin stab: Napiform liquefaction. 

Agar colonies: Yellowish, circular, 
smooth, entire, iridescent. 

Agar slant: Light yellow, transparent 
streak. 



FAMILY VII. SPIRILLACEAE 



245 



Broth: Slightly turbid; thin pellicle. 

Litmus milk: Soft coagulum. Peptonized, 
alkaline. 

Potato : Brownish red streak. 

Indole produced. 

Hj^drogen sulfide produced. 

No action in sugar media. 

Nitrites not produced from nitrates. 

Pathogenic for frogs. 

Aerobic, facultative. 

Optimum temperature, between 18° and 
20° C. 

Habitat: Causes epidemic infection in 
fish. 

29. Vibrio hyphalus ZoBell and Up- 
ham, 1944. (Bull. Scripps Inst, of Ocean- 
ography, Univ. Calif., 5, 1944, 277.) 

hy.pha'lus. Gr. adj. hyphalus under the 
sea, submarine. 

Curved rods, 0.6 by 1.6 to 4.0 microns, 
with rounded ends, occurring singly. Motile 
by means of one or occasionally two polar 
fiagella. Granular staining. Gram-negative. 

Note: All differential media e.xcept the 
fresh-water broth, litmus milk and potato 
were prepared with sea water. 

Gelatin colonies: Circular or irregular 
with liquefaction; yellowish gray. 

Gelatin stab: Napiform liquefaction. 
Filiform growth along line of stab. 

Agar colonies: 2 to 3 mm in diameter, 
circular, undulate, convex, radial folds, 
smooth. 

Agar slant: Abundant, echinulate, glis- 
tening, gummy growth with pale pink pig- 
ment. 

Sea-water broth: Scant pellicle; moder- 
ate turbidity; moderate, flocculent sedi- 
ment. 

Fresh-water broth: No visible growth. 

Litmus milk: No visible change. 

Potato: No visible growth. 

Indole not produced. 

Hydrogen sulfide is produced. 

No acid or gas from glucose, sucrose, lac- 
tose, glycerol, xylose, mannitol or salicin. 

Starch not hydrolyzed. 

Non-lipolytic. 

Nitrites produced from nitrates. 

Ammonia produced from peptone but 
not from urea. 

Casein is digested. 



Aerobic, facultative. 

Optimum temperature, between 20° and 
25° C. 

Source: Isolated from marine bottom 
deposits. 

Habitat: Probably widely distributed. 

30. Vibrio fetus Smith and Taylor, 1919. 
(Spirillum causing abortion in sheep, Mac- 
Fadyean and Stockman, Rept. Dept. Comm. 
Ministry Agric. on Epizootic Abortion, 
London, 1909, 156; also see MacFadyean 
and Stockman, ibid., 1913, 111; Spirillum 
associated with infectious abortion. Smith, 
Jour. Exp. Med., 28, 1918, 701; Smith and 
Taylor, ibid., 30, 1919, 299.) 

fe'tus. L. noun fetus a fetus; L. mas. gen. n. 
fetus of a fetus. 

Description taken primarily from Plast- 
ridge, Williams, Easterbrooks, Walker and 
Beccia (Storrs Agr. Exp. Sta., Bull. 281, 
1951, 11) and from Rhoades (Bact. Proc, 
53rd Gen. Meeting, Soc. Amer. Bact., San 
Francisco, 1953, 34). 

Curved rods that are minute, comma- 
and S-shaped forms on initial isolation. 
On transfer, very long, filamentous forms 
may appear. 0.2 to 0.5 by 1.5 to 5.0 microns. 
Motile, the comma forms possessing a single, 
polar fiagellum, and the S forms usually 
possessing a single fiagellum at each pole. 
Prolonged incubation and transfer to dry 
slants or semisolid media produces coccoid 
forms with one or more fiagella. Occasion- 
ally encapsulated. Granules present in older 
cultures. Gram-negative. 

Gelatin: No or poor growth on ordinary 
gelatin; with the addition of proper nutri- 
ments, good to excellent growth may occur 
in 3 to 5 days. No liquefaction. 

Agar plates: No growth. Reich, Morse and 
Wilson (Amer. Jour. Vet. Res., 17, 1956, 
140), however, report growth when cultures 
are incubated in an atmosphere of either 
helium or nitrogen. 

Agar slant: No surface growth by freshly 
isolated strains; laboratory strains produce 
a scant, grayish white, glistening surface 
growth. Good growth is obtained when 
cultures are incubated in an atmosphere of 
helium or nitrogen (Reich et al., loc. cit.). 

Sub-surface agar colonies: Small, yellow, 
opaque. 



246 



ORDER I. PSEUDOMONADALES 



Blood agar plates (in 10 per cent CO2 
atmosphere) : Growth. 

Thiol agar (prepared by adding 35.0 gm 
of granular agar and 0.05 gm of glutathione 
to 1.0 liter of thiol medium (supplied in 
dehydrated form by Difco Laboratories) 
and adjusting the pH to 8.9): Moderate 
growth. Colonies vary from small (1 mm in 
diameter), transparent and convex to trans- 
lucent or opaque, light tan colonies up to 
3 mm in diameter. Masses of growth are 
translucent and light gray or light tan. 

Broth: A viscid ring pellicle may appear; 
faint clouding of the medium occurs; a 
filmy, stringy deposit may settle out. 

Litmus milk: No growth. 

Potato: No growth. 

Indole not produced. 

Hydrogen sulfide not produced. 

Nitrites produced from nitrates (Bryner 
and Frank, Amer. Jour. Vet. Res., 16, 1955, 
76). 

Blood serum slant: Feeble growth. No 
liquefaction. 

No gas from carbohydrates. No change 
or slightl.y acid from glucose, lactose and 
sucrose. No acid from the following carbo- 
hydrates when each was added to a medium 
of beef infusion with peptone, agar and 
Andrade's indicator: glucose, fructose, 
galactose, arabinose, raffinose, trehalose, 
sucrose, maltose, lactose, dextrin, inulin, 
salicin, dulcitol, mannitol and sorbitol. 

Temperature relations: Optimum, 37° C. 
Minimum, 15° C. Maximum, 40.5° C. With- 
stands 55° C. for 5 minutes. 

Strains isolated from cases of abortion 
are catalase-positive (Bryner and Frank, 
loc. cit.). 

Salt tolerance: Tolerates 1.5 to 2.0 per 
cent NaCl in a semisolid medium. 

Bile tolerance: Most strains grow in a 
semisolid medium containing 10 per cent 
fresh ox bile; all strains grow in 5 per cent 
ox bile media (Schneider and Morse, Cor- 
nell Vet., J!^5, 1955, 84). 

Aerobic to microaerophilic. 

Pathogenicity: Infection with Vibrio 
fetus (vibriosis) causes abortion in cattle 
and sheep. Pathogenic for guinea pigs, ham- 
sters and embryonated chicken eggs (see 
Webster and Thorp, Amer. Jour. Vet. Res., 



14, 1953, 118; Ristic and Morse, ibid., 399; 
and Ristic, Morse, Wipf and McNutt, ibid., 

15, 1954, 309). Non-pathogenic to rabbits, 
rats and mice when injected intraperitone- 
ally. 

Source: Twenty-two strains were isolated 
from the placentas or fetuses of cows having 
abortion. 

Habitat: Causes abortion in cattle and 
sheep. 

31. Vibrio coli Doyle, 1948. (Comma- 
shaped microorganisms. Whiting, Doyle 
and Spray, Purdue Univ. Agr. Exp. Sta. 
Bull. 257, 1921, 12; Vibrio of swine dysen- 
tery, Doyle, Amer. Jour. Vet. Res., 5, 1944, 
3; Doyle, ibid., 9, 1948, 50.) 

co'li. Gr. noun colum or colon the large 
intestine, colon; M.L. gen. noun coli of the 
colon. 

Description taken from Doyle {loc. cit.) 
and Hauduroy et al. (Diet. d. Bact. Path., 
2nd ed., 1953, 649). 

Curved rods, comma- and sometimes 
spiral-shaped, 0.2 to 0.5 by 1.5 to 5.0 mi- 
crons. Motile by means of a single, polar 
flagellum. Gram-negative. 

Agar colonies: Transparent and color- 
less. Good growth only when the medium 
contains 10 per cent of defibrinated blood 
and when the atmosphere contains 15 per 
cent CO2 ; abundant growth in the moisture 
of condensation. 

Gelatin: Not liquefied. 

Litmus milk: No growth; not coagulated. 

Indole not produced. 

Glucose, sucrose, lactose, maltose and 
mannitol not utilized. 

Nitrites not produced from nitrates. 

Coagulated blood serum not hemolyzed. 

Pathogenicity: Injection causes no dis- 
ease in calves, rabbits, rats, mice, guinea 
pigs or chickens. Injection causes dj-sentery 
in swine. 

Source: Isolated from the mucosa of the 
colon of a swine which had died of dys- 
entery. 

Habitat: Causes dysentery in swine. 

32. Vibrio jejuni Jones et al., 1931. 
(Jones, Orcutt and Little, Jour. Exp. Med., 
53, 1931, 853.) 



FAMILY VII. SPIRILLACEAE 



247 



je.ju'ni. L. adj. jejunus insignificant, 
meagre; ALL. noun jejunuin the jejunum. 

Pleomorphic, occurring in three different 
form.s in the same culture: the first forms 
are short, slightly convoluted and activel}^ 
motile with either a single polar flagellum 
or a single flagellum at each pole; the sec- 
ond are less active and have two or more 
complete coils; the remaining forms are 
extremely long and rarely motile. In older 
cultures clumps occur, and these usually 
degenerate into fragments and granules. 
Gram-negative. 

Blood agar: Within 4 or 5 days the con- 
densation fluid becomes slightly turbid; 
delicate lines then appear at the border of 
the agar. After several transfers these lines 
Ijecome well defined, and a delicate film 
spreads over the nether portion of the slant. 

Gelatin: Not liquefied. 

Coagulated blood serum not lifiuefied. 

Carbohydrates not utilized. 

Aerobic. 

Optimum pH, 7.6. No growth in either 
slightly acid or definitely alkaline media. 

Temperature relations : Optimum, 37.5° C. 
(Merchant, Vet. Bact. and Virology, 4th 
cd., 1950, 343). Killed in 5 minutes at 55° C. 

Pathogenicity: Non-pathogenic to lab- 
oratory animals under the usual conditions. 
Some strains produce multiple necrotic foci 
of the liver when injected intraperitoneally 
into white mice. Febrile reactions are pro- 
duced in rabbits when injected intrave- 
nously with certain strains. The enteritis 
produced experimentally in calves is less 
severe than that occurring spontaneously. 

Source: Isolated from the small intestine 
of calves suffering from diarrhoea. 

Habitat: Causes diarrhoea in cows and 
calves where it is found in the small in- 
testine and feces. 

33. Vibrio niger (Rist, 1898) Prevot, 
1948. (Spirillum nigrum Rist, These med., 
Paris, 1898; also see Cent. f. Bakt., I Abt., 
30, 1901, 299; Prevot, Man. d. Classif. Bact. 
Anaer., 2nd ed., 1948, 124.) 

ni'ger. L. adj. niger black. 

Description taken from Rist (op. cil., 
1901, 299) and Hauduroy et al. (Diet. d. 
Bact. Path., 2nd ed., 1953, 658). 



Long, slender, comma- or S-shaped cells 
rounded at the ends; 1.0 to 2.0 by 3.0 mi- 
crons. Motile. Possess a black granule which 
swells the cell and which may be terminal. 
Gram-negative. 

Glucose agar colonies: Lenticular, dark 
black, opaque, 2 to 3 mm in diameter. 

Deep agar colonies: Lenticular, black, 
cloudy; gas is produced. 

Deep blood serum agar colonies: Small, 
thin, delicate, non-hemolytic. 

Brain medium: Blackened; hydrogen 
sulfide, ethanol and butyric and lactic acids 
are produced. 

Gelatin colonies: Black, opaque; putrid 
odor. No liquefaction. 

Glucose broth: Dark gray turbidity; 
putrid odor; gas and hydrogen sulfide are 
produced. 

Peptone broth: Poor growth. 

Milk: Coagulated slowly then digested. 

Coagulated ascitic fluid: Not liquefied. 

Indole not produced. 

Hydrogen sulfide produced. 

Neutral red reduced. 

Obligate anaerobe. 

Temperature relations: Growth range, 
21° to 37° C. Death occurs at 55° C. Can 
withstand freezing. 

Pathogenicity: Fatal for guinea pigs in 
two weeks; macroscopic lesions not demon- 
strable. 

Source: Isolated from purulent otitis, 
mastoiditis and pulmonary gangrene; also 
isolated from cases of meningitis and appen- 
dicitis. 

Habitat: Found rather frequently in man 
under pathological conditions. 

34. Vibrio sputoruin Prevot, 1940. (An 
anaerobic vibrio from bronchitis, Tunni- 
cliff. Jour. Inf. Dis., 15, 1914, 350; A small 
anaerobic vibrio from Vincent's angina. 
Smith, ibid., Jfi, 1930, 307; Prevot, Man. de 
Classif. des Bact. Anaer., Paris, 1940, 85.) 

spu.to'rum. L. noun sputum spit, spu- 
tum; L. gen.pl. noun sputorum of sputa. 

Description taken from Prevot {loc. cit.) 
and from Macdonald (Motile, Non-sporu- 
lating. Anaerobic Rods of the Oral Cavity, 
Toronto, 1953, 53). 

Straight or slightly curved rods, 0.5 to 



248 



ORDER I. PSEUDOMONADALES 



0.8 by 2.0 to 8.0 microns, occurring singly, 
in pairs or in short chains. Active, darting 
motility by means of 1 to 3 polar flagella. 
Gram-negative. 

Grows only in media to which body fluids 
(blood, ascites, etc.) have been added or in 
other enriched media. 

Ascitic fluid broth: Almost imperceptible 
turbidity. 

Thioglycollate broth: Light, floccular 
turbidity. 

Blood agar colonies : After 5 days, smooth, 
convex, grayish yellow, dull and translucent 
with a finely fimbriate margin. Less than 
0.5 mm in diameter. Frequently surrounded 
by a narrow zone of green. 

Coagulated blood serum: Cloth-like 
growth. No odor. 

Genus II. Desulfovibrio Kluyver and van Niel, 1936.* 

(Kluyver and van Niel, Zent. f. Bakt., II Abt., H, 1936, 369; Sporovibrio 
Starkey, Arch. f. Mikrobiol., 9, 1938, 300.) 

De.sul.fo.vib'ri.o. L. pref. de from; L. sulfur sulfur; L. v. vibro to vibrate; M.L. mas.n. 
Vibrio that which vibrates, a generic name; M.L. mas.n. Desulfovibrio a vibrio that reduces 
sulfur compounds. 

Slightly curved rods of variable length, usually occurring singly but sometimes in short 
chains which have the appearance of spirilla. Swollen pleomorphic forms are common. 
Actively motile by means of a single polar flagellum. Strict anaerobes which reduce sulfates 
to hydrogen sulfide. Found in sea water, marine mud, fresh water and soil. 

The type species is Desulfovibrio desulfuricans (Beijerinck) Klu3^ver and van Niel. 



Nitrites produced from nitrates by some 
strains. 

Indole not produced. 

Hydrogen sulfide produced. 

Carbohydrates not utilized. 

Optimum pH, 7.2. Feeble growth between 
pH 6.0 and 9.7. 

Serology: Cross-reacting, somatic anti- 
gens have been demonstrated. 

Anaerobic. 

Optimum temperature, 37° C. Growth 
feeble at 27° and 45° C. No growth at 20° C. 

Source: Isolated by Pr^vot from a case of 
bronchitis. 

Habitat: Found in the human oral cavity 
and in fusospirochetal diseases of the mouth. 



1. Desulfovibrio desulfuricans (Beijer- 
inck, 1895) Kluyver and van Niel, 1936. 
(Bacterium hydrosulfureum ponticum Zelin- 
sky, Proc. Russ. Phys. and Chem. Soc, 25, 
1893, 298; Spirillum desulfuricans Beijer- 
inck, Cent. f. Bakt., II Abt., 1, 1895, 1; 
Kluyver and van Niel, Zent. f. Bakt., II 
Abt., 94, 1936, 369; Sporovibrio desulfuricans 
Starkey, Koninkl. Nederland. Akad. v. 
Wetenschappen, Proc, 41, 1938, 426; also in 
Arch. f. Mikrobiol., 9, 1938, 268.) 

de.sul.fur'i.cans. L. pref. de from; L. 
noun sulfur sulfur; M.L. part. adj. desul- 
furicans reducing sulfur compounds. 

Slightly curved rods, 0.5 to 1.0 by 1 to 5 
microns, usuall}- occurring singly but some- 
times in pairs and short chains which cause 
them to look like spirilla. Swollen pleomor- 



phic forms are common. Older cells appear 
black due to precipitated ferric sulfide. 
Actively motile, possessing a polar flagel- 
lum. Stains readily with carbol fuchsin. 
Gram-negative. 

Gelatin: No liquefaction. 

Grows best in fresh-water media. Fails to 
develop in sea water upon initial isolation. 

Produces opalescent turbidity in absence 
of oxygen in mineral media enriched with 
sulfate and peptone. 

Media containing iron salts and sulfur 
compounds blackened. Bacteria found asso- 
ciated with precipitated ferrous sulfide. 

Peptone-glucose agar colonies (in absence 
of air) : Small, circular, slightly raised, dull, 
entire, soft in consistency. 

Peptone, asparagine, glycine, alanine, 



* Prepared by Dr. Claude E. ZoBell, Scripps Institution of Oceanography, La Jolla, Cali- 
fornia, January, 1943; revised January, 1953. 



FAMILY VII. SPIRILLACEAE 



249 



aspartic acid, ethanol, propanol, butanol, 
glycerol, glucose, lactate, succinate and 
malate known to be utilized as hydrogen 
donors. Some varieties oxidize H2 . 

Produces up to 3100 mg HjS per liter. 

Nitrites not produced from nitrates. 

Reduces sulfate to hydrogen sulfide; 
also reduces sulfites, thiosulfates and 
hyposulfites. 

Temperature relations: Optimum, be- 
tween 25° and 30° C. Maximum, between 
35° and 40° C. 

Chemical tolerance: Optimum pH, be- 
tween 6 and 7.5. Limits for growth, between 
pH 5 and 9. 

Cytochrome is produced. 

Anaerobic. 

Habitat : Soil, sewage and water. 

2. Desulfovibrio aestuarii (van Delden, 
1904; ZoBell, 1948. (Microspira aestuarii van 
Delden, Cent. f. Bakt., II Abt., 11, 1904,81; 
ZoBell, in Manual, 6th ed., 1948, 208.) 

aes.tu.a'ri.i. L. noun uestuarium an 
estuary, inlet; L. gen. noun aestuarii of an 
estuary. 

Morphologically indistinguishable from 
Desulfovibrio desulfuricans described above, 
although it has a greater tendency to pleo- 
morphism and is slightly larger. Motile, 
possessing a polar flagellum. Gram-nega- 
tive. 

Gelatin: No liquefaction. 

Grows preferentially in media prepared 
with sea water or 3 per cent mineral salt 
solution enriched with sulfate and peptone. 
According to Baars (Over Sulfaatreductie 
door Bakterien, Diss. Delft, 1930, 164 pp.) 
the marine species can be acclimatized to 
tolerate hj^potonic salt solutions, but Rit- 
tenberg (Studies on Marine Sulfate- 
Reducing Bacteria, Thesis, Univ. of Calif., 
1941, 115 pp.) was unable to confirm this 
observation. Likewise Rittenberg was 
unable to acclimatize D. aestuarii to tolerate 
temperatures exceeding 45° C. or to produce 
endospores. 

Produces faint turbidity in absence of 
oxygen in sea water enriched with sulfate 



and peptone. Organisms most abundant in 
sediment. 

Agar colonies: Small, circular, slightly 
raised, darker centers, entire, soft con- 
sistency. 

Peptone, asparagine, glycine, alanine, 
glucose, fructose, ethanol, butanol, gh^cerol, 
acetate, lactate and malate known to be 
utilized in presence of sulfate. Some strains 
utilize molecular hydrogen as the sole source 
of energy. 

Reduces sulfate to hj'drogen sulfide. Also 
reduces sulfites, thiosulfates and hy- 
posulfites. 

Produces up to 950 mg of hydrogen sulfide 
per liter. 

Nitrites not produced from nitrates. 

Temperature relations: Optimum, be- 
tween 25° and 30° C. Maximum, between 
35° and 40° C. 

Chemical tolerance: Optimum pH, be- 
tween 6 and 8. Limits for growth, between 
pH 5.5 and 8.5. 

Anaerobic. 

Habitat: Sea water, marine mud, brine 
and oil wells. 

3. Desulfovibrio rubentschikii (Baars, 

1930) ZoBell, 1948. {Vibrio riibentschickii 
(sic) Baars, Over Sulfaatreductie door Bak- 
terien, Diss. Delft, 1930, 89; ZoBell, in Man- 
ual, 6th ed., 1948, 208.) 

ru.ben.tschi'ki.i. M.L. gen. noun ruben- 
tschikii of Rubentschik; named for Dr. L. 
Rubentschik. 

Slightly curved rods, 0.5 to 1.0 by 1 to 5 
microns, usually occurring singly, some- 
times in pairs and short chains. Actively 
motile, possessing a polar flagellum. Gram- 
negative. Morphologically indistinguishable 
from Desulfovibrio desulfuricans. 

Reduces sulfate to hydrogen sulfide; also 
reduces sulfites, thiosulfates and hypo- 
sulfites. 

Culturally and phj'siologically like D. 
desulfuricans except that D. rubentschikii 
utilizes propionic, butyric, valeric, palmitic 
and stearic acids and galactose, sucrose, 
lactose and maltose. 

Anaerobic. 

Habitat: Soil and ditch water. 



250 ORDER I. PSEUDOMONADALES 

Genus III. Methanobacterium Kluyver and van Niel, 1936* 
(Zent. f. Bakt., II Abt., 94, 1936, 399.) 

Me.tha.no.bac.te'ri.um. Gr. noun iiiethy wine; M.L. noun methanum methane; Gr. 
neut.n. bacterium a small rod; M.L. noun Methanobacterium the methane (-producing) 
rodlet. 

Straight or slightly curved rods, sometimes united in bundles or long chains. Reported to 
be non-motile. Anaerobic. Chemo-heterotrophic or chemo-autotrophic, oxidizing various 
organic or inorganic compounds and reducing carbon dioxide to methane. Gram-negative. 

The anaerobic genus Methanobacterium was proposed by Kluyver and van Niel in 1936 with 
an indication that they regarded Sohngen's methane bacterium as the type species of the 
genus. Later, Barker (1936) found organisms that he regarded as identical with those pre- 
viously isolated by Sohngen, and he proposed the name Methanobacterium sohngenii for this 
species. While the organisms belonging to this genus are reported to be non-motile, the 
curved form of their cells and their physiology places them near the species placed in De- 
suFovibr-io. 

The type species is Methanobacterium soehngenii Barker. 

1. Methanobacterium soehngenii Acetate and n-butyrate but not pro- 
Barker, 1936. (Methane bacterium, Sohn- pionate are fermented with the production 
gen, Dissertation, Delft, 1906; Barker, Arch. of methane and carbon dioxide, 
f. Mikrobiol., 7, 1936, 433.) Ethyl and n-butyl alcohols not fermented. 

soehn.ge'ni.i. M.L. gen.noun soehngenii Obligate anaerobe, 

of Sohngen; named for Prof. N. L. Sohngen, g^^^.^^ . Enrichment cultures containing 

the bacteriologist who first studied this acetate or butyrate as the only organic com- 

?,,■., ,. , , , , pound. Four strains were isolated from ace- 
Rods straight to slightly curved, moder- "■' . . ^ ,^ rr,, ,., 
^ , , ,, ,., ^, ,. tate enrichment cultures. The cultures were 
ately long. ISon-motile. Gram-negative. .^ , , . , 

In liquid cultures, cells are character- highly purified but not strictly pure, 
istically joined into long chains which often Habitat: Canal mud, sewage. Probably 

lie parallel to one another so as to form occurs widely in fresh-water sediments 

bundles. where anaerobic conditions prevail. 

Genus IV. Cellvibrio Winogradsky, 1929.] 
(Ann. Inst. Pasteur, J^S, 1929, 577.) 

Cell.vib'ri.o. L. noun cella a room, cell; L. v. vibro to vibrate; M.L. mas.n. Vibrio that 
which vibrates, a generic name; M.L. mas.n. Cellvibrio cell vibrio, but here the cell is an 
abbreviation of cellulose, hence, cellulose vibrio. 

Long slender rods, slightly curved, with rounded ends, showing deeply staining granules 
which appear to be concerned in reproduction. Monotrichous. Most species produce a yellow 
or brown pigment with cellulose. Oxidize cellulose, forming oxycellulose. Growth on ordi- 
nary culture media is feeble. Found in soil. 

The type species is Cellvibrio ochraceus Winogradsky. 

Key to the species of genus Cellvibrio. 

I. No growth on glucose or starch agar. 

A. Ochre-yellow pigment produced on filter paper. 

1. Cellvibrio ochraceus. 

* Revised by Prof. Robert S. Breed, Cornell University, Geneva, New York, May, 1955. 
t Revised by Prof. Robert S. Breed, Cornell University, Geneva, New York, with the 
assistance of Prof. Onorato Verona, University of Pisa, Pisa, Italy, September, 1953. 



FAMILY VII. SPIRILLACEAE 



251 



II. Growth on glucose and starch agar. 

A. Poor growth on starch agar. 

1. Cream-colored pigment which becomes brown with age is produced on filter paper. 

2. Cellvibrio flavescens. 

B. Abundant growth on starch agar. 

1. Scant growth on glucose agar. 

a. Intense yellow pigment produced on filter paper. 

3. Cellvibrio fulvus. 

2. Abundant growth on glucose agar. 

a. No pigment produced on filter paper. 

4. Cellvibrio vulgaris. 



1. Cellvibrio ochraceus Winogradsky, 
1929. (Ann. Inst. Pasteur, 43, 1929, 549, 601.) 

och.ra'ce.us. Gr. noun ochra ochre; M.L. 
adj. ochraceus like ochre, rust-colored. 

Plump, curved rods with rounded ends, 
2.0 to 4.0 microns long, rarely occurring as 
spirals. Chromatic granule frequently found 
in center. Motile by means of a single flagel- 
lum. Gram-negative. 

Produces diffuse, light ochre-colored, 
mucilaginous colonies on cellulose silica gel 
medium. 

No action or growth on plain agar. No 
growth on peptone, glucose, starch or 
tragacanth gum agar. 

Grows well on hydrocellulose agar without 
producing clearings. 

Cellulose is oxidized to acid oxycellulose 
without the production of reducing sub- 
stances or volatile by-products; a soluble, 
non-reducing product may be formed. 

Filter paper streaks : Entire paper colored 
ochre-yellow in 48 hrs. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Distinctive character: Rapid, ochre- 
colored growth. 

Habitat: Soil. Disintegrates vegetable 
fibers. 

2. Cellvibrio flavescens Winogradsky, 
1929. (Ann. Inst. Pasteur, 43, 1929, 608.) 

fla.ves'cens. L. v. flavesco to become 
golden yellow; L. part. adj. flavescens be- 
coming yellow. 

Plump, curved rods, flexuous, with 
rounded ends, 0.5 by 2.5 to 5.0 microns. 
Show metachromatic granules. Motile by 
means of a single flagellum. Gram-negative. 

Produces diffuse, cream-colored growth 



becoming brownish; mucilaginous colonies 
on cellulose silica gel medium. 

Good growth on peptone agar. Colonies 

I mm in 4 days. Grows poorly on glucose, 
starch and gum agars. 

Filter paper streaks: Almost as rapid in 
growth as Cellvibrio ochraceus and colors 
entire paper in 2 to .3 days. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Distinctive characters: Smaller, less 
curved rods which grow on a greater variety 
of media than Cellvibrio ochraceus but which 
do not attack cellulose as readily. 

Source: Isolated from a pile of old damp 
sawdust. A variety of this organism has been 
isolated from sea water by Kadota (Bull. 
Japan. Soc. Sci. Fish., 16, 1951, 63-70). 

Habitat: Soil. Disintegrates vegetable 
fibers. 

3. Cellvibrio fulvus Stapp and Bortels, 
1934. (Culture Y, Dubos, Jour. Bact., 15, 
1928, 230; Stapp and Bortels, Zent. f. Bakt., 

II Abt.,50, 1934,42.) 

ful'vus. L. ad}, fulvus deep yellow. 

Slightly curved rods, 0.3 to 0.4 by 1.5 to 
3.0 microns. Show involution forms. Motile 
by means of a single, polar flagellum. Gram- 
negative. 

Cellulose is decomposed. Grows on filter 
paper with an intense egg-yellow color 
which in older cultures may deepen to rust 
brown. 

Glucose agar: Very scant growth. 

Sucrose agar: Very slight growth. 

Maltose agar: Abundant yellow growth. 

Lactose agar: Fairly abundant yellow 
growth. 



252 



ORDER I. PSEUDOMONADALES 



Starch agar: Very abundant, In-ight 
vellow growth which later turns brown. 

Nutrient broth: No growth. 

Temperature relations: Optimum, be- 
tween 25° and 30° C. Minimum, 5° C. Maxi- 
mum, between 32° and 35° C. No growth at 
37° C. Thermal death point, between 39° 
and 40° C. 

Aerobic. 

Source: Isolated from forest soil in Ger- 
many and from soil in the United States. 

Habitat: Widely distributed in soils. 

4. Cellvibrio vulgaris Stapp and Bor- 
tels, 1934. (Culture Co, Dubos, Jour. Bact., 
15, 1928, 230; Stapp and Bortels, Zent. f. 
Bakt., II Abt., 50, 1934,44.) 

vul.ga'ris. L. adj. vulgaris common. 

Curved rods, 0.3 by 2.9 to 4.0 microns. 
Show involution forms. Motile by means of 
a single polar flagellum. Gram-negative. 



Cellulose is decomposed. Grows on filter 
paper without the formation of pigment. 

Glucose agar: Abundant growth. No pig- 
ment. 

Sucrose agar: Abundant, slightly yellow 
growth. 

Maltose agar: Abundant, .yellowish 
growth. 

Lactose agar: Very heavy growth. 

Starch agar: Very abundant, yellowish 
growth. 

Nutrient broth: No growth. 

Temperature relations: Optimum, be- 
tween 25° and 30° C. Minimum, 5° C. Maxi- 
mum, between 32° and 35° C. No growth at 
37° C. Thermal death point, between 44° 
and 45° C. 

Aerobic. 

Source: Isolated from forest soil in Ger- 
many and from soils in the United States. 

Habitat: Widelv distributed in soils. 



Genus V. Cellfalcicula Winogradsky, 1929.* 
(Ann. Inst. Pasteur, 43, 1929, 616.) 

Cell.fal.ci'cu.la. L. noun cella a room, cell; M.L. noun ceUulosum cellulose; L. noun 
falcicula a sickle; M.L. fem.n. Cellfalcicula cell sickle, but here the cell is an abbreviation of 
cellulose, hence, cellulose sickle. 

Short rods or spindles, not exceeding 2 microns in length, with pointed ends, containing 
metachromatic granules. Old cultures show coccoid forms. Monotrichous. Oxidize cellulose, 
forming oxycellulose. Growth on ordinary culture media is feeble. Soil bacteria. 

The type species is Cellfalcicula viridis Winogradsky. 



1. Cellfalcicula viridis Winogradsky, 
1929. (Ann. Inst. Pasteur, 43, 1929, 616.) 

vi'ri.dis. L. adj. viridis green. 

Plump, small spindles, 0.7 by 2.0 microns, 
with rounded ends. Motile by means of a 
single flagellum. Gram-negative. 

Produces diffuse green, mucilaginous 
colonies on cellulose silica gel medium. 

Filter paper streaks: Rapid spreading 
growth colored green in 3 days at 30° C. 

Hydrocellulose agar: Growth rapid, 
green; minute, yellowish green, mucous 
colonies on streaking. 

No growth on peptone, glucose, starch 
or gum agar. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Habitat: Soil. 



2. Cellfalcicula mucosa Winogradsky, 
1929. (Ann. Inst. Pasteur, 43, 1929, 621.) 

mu.co'sa. L. adj. mucosus slimy. 

Plump, curved spindles, with slightly 
pointed ends. Motile by means of a single 
polar flagellum. Contain a single chromatic 
granule. Gram-negative. 

Produces diffuse, cream-colored, muci- 
laginous colonies on cellulose silica gel 
medium. 

Hydrocellulose agar: Abundant grayish 
growth. 

No growth on peptone, glucose, starch or 
gum agar. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Habitat: Soil. 



* Revised by Prof. Robert S. Breed, Cornell LTniversity, Geneva, New York, September, 
1937. 



FAMILY VII. SPIRILLACEAE 



253 



3. Cellfalcicula fusca Winogradsky, 
1929. (Ann. Inst. Pasteur, A3, 1929, 622.) 

fus'ca. L. adj. fuscus dark, tawny. 

Plump, curved spindles, 0.5 by 1.2 to 2.5 
microns, with slightly pointed ends and a 
central chromatic granule. Motile by means 
of a single, polar flagellum. Gram-negative. 

Produces diffuse, brownish, slightly 
marbled or veined colonies on cellulose silica 
gel medium. 



Filter paper streak: Paper becomes a 
partially transparent, dry, non-mucilagi- 
nous pellicle adherent to gel. 

Aerobic, facultative. 

Optimum temperature, 20° C. 

Source: Isolated from a pile of old, damp 
sawdust. 



Habitat: Probably rotting wood. 
Genus VI. Microcyclus 0rskov, 1928.* 

(Cent. f. Bakt., I Abt., Orig., 107, 1928, 180; also see Riassunti d. Communicazioni, 
VI Cong. Internaz. d. Microbiol., Roma, 1, 1953, 24.) 

Micro. cyc'lus. Gr. adj. micrus small, little; Gr. cyclus round, circle; M.L. mas.n. Mic- 
rocyclus small circle. 

Small, slightly curved, non-motile rods which form a closed ring during growth. These 
rings grow into bodies which subdivide again into rod-shaped elements as at the beginning. 
Encapsulated. Attack few sugars and then only slowly. From fresh-water ponds and from 
soil. 



The type species is Microcyclus aquaticus ^rskov. 



1. Microcyclus aquaticus 0rskov, 1928. 
(Cent. f. Bakt., I Abt., Orig., 107, 1928, 180; 
also see Riassunti d. Communicazioni, VI 
Cong. Internaz. d. Microbiol., Roma, 1, 
1953, 24.) 

a.qua'ti.cus. L. adj. aquaticus living in 
water. 

Very small, slightly curved rods about 1 
micron in length. During growth, the rods 
form closed rings 2 to 3 microns in diameter. 
The next stage is a body consisting of horse- 
shoe-shaped halves that are fastened to- 
gether without visible divisional lines. 
These halves further subdivide into separate 
rods ; the rods then form rings and start the 
cycle of growth all over again. Form and 
capsule are seen most distinctly with direct 
agar microscopy and direct India ink agar 
microscopy. Encapsulated. Non-motile. 
Gram-negative. 

Gelatin: No liquefaction in one month. 



butyrous. This species is not fastidious in its 
growth requirements, although colonies are 
small. It grows well on tap-water agar plus 
0.5 per cent peptone. 

No acid from glucose, sucrose, lactose, 
maltose, adonitol, dulcitol, sorbitol, inosi- 
tol, rhamnose and salicin. After six weeks, 
slight acid in arabinose and xylose. 

Indole not produced. 

Non-hemolytic. 

Grows at temperatures between 5° and 
30° C. No growth at 37° C. 

Source: Originally found in the waters of 
a woodland lake. Later isolated from fresh- 
water ponds and occasionally from soil. 
Sturges (Absts. of Bact., 7, 1923, 11) briefly 
reports the presence of organisms with the 
same unusual morphology in ham-curing 
brines. 

Habitat: Presumably widely distributed 
in fresh water and in soil. 



Agar colonies: Round, smooth edges. 

Genus VII. Spirillum Ehrenberg, 1832.^ 
(Physik. Abhandl. k. Akad. Wissensch. Berlin, 1832, 38.) 
Spi.ril'lum. Gr. noun spira a spiral; M.L. dim.neut.n. Spirillum a small spiral, generic 
name. 

* Prepared by Dr. J. 0rskov, Director, Statens Seruminstitut, Copenhagen, Denmark, 
November, 1953. 

t Revised by Prof . Robert S. Breed, Cornell University, Geneva, New York, April, 1954, 
based on a Monograph by Giesberger, Inaug. Diss., Delft, Nov. 30, 1936. 



254 ORDER I. PSEUDOMONADALES 

Cells form either long screws or portions of a turn. Volutin granules are usually present. 
Usually motile by means of a tuft of polar flagella (5 to 20) which may occur at one or both 
ends of the cells. Aerobic, growing well on ordinary culture media except for one saprophyte 
and the pathogenic species; these have not yet been cultivated. Usually found in fresh and 
salt water containing organic matter. 

The type species is Spirillum undula (Miiller) Ehrenberg. 

Key to the species of genus Spirillum. 

I. One micron or less in diameter. 

A. Volutin granules present. 

1. Slow to rapid liquefaction of gelatin. 

a. Grajash to brown growth on potato. 

1. Spirilluni undula. 
aa. Light yellowi.sh orange growth on potato. 

2. Spirillum serpens. 

2. No liquefaction of gelatin. Of small size (0.5 micron in diameter). 

a. Colonies on agar white becoming brownish black and slightly wrinkled. 

3. Spirillum itersonii. 
aa. Colonies on agar white and smooth. 

4. Spirillum tenue. 

B. No volutin granules observed. 

1. Single fiagellum. From sea water. 

5. Spirillum virginianum. 

2. Tuft of flagella. From blood of rats and mice. 

6. Spirillum minus. 
II. Over 1 micron in diameter. 

A. Grow poorly or not at all on peptone agar media. 

1. Grows poorly on peptone agar and potato. 

7. Spirillum kutscheri. 

2. Has not been cultivated on artificial media. Very evident volutin granules. 

8. Spirillum volutans. 

B. Grows abundantly on peptone media. Cells may be deformed with fat droplets. 

9. Spirillum lipoferum. 

1. Spirillum undula (Miiller, 1786) Agar colonies: Grayish white, smooth. 

Ehrenberg, 1832. {Vibrio undula Miiller, Broth: Turbid. 

Animalcula infusoria et marina, 1786; Potato: Grayish brown growth. 

Ehrenberg, Physik. Abhandlungen d. k. Indole not produced. 

Berl. Akad., 1832, 38.) Catala.se-positive. 

un'du.la. L. noun unda a wave; M.L. Nitrites not produced from nitrates, 

dim.fem.n. undula a small wave. Aerobic, facultative. 

Stout threads, 0.9 micron in diameter, Optimum temperature, 25° C. 

with one-half to three turns. The wave Cohn (Beitrage z. Biol. d. Pflanzen, 1, 

lengths are 6 microns. Width of spiral, 3.0 Heft 2, 1875, 132) reports that he could not 

microns. Tufts of three to nine flagella at distinguish this organism from Vibrio 

each pole. Volutin granules present. Gram- prolifer Ehrenberg. 

negative. Habitat: Putrid and stagnant water. 

Gelatin colonies: The surface colonies are 

circular, granular, greenish yellow, entire. 2. Spirillum serpens (Miiller, 1786) 

Gelatin stab: Thick, white, rugose sur- Winter, 1884. {Vibrio serpens Miiller, Ani- 

face growth. Very slow liquefaction. malcula infusoria et marina, 1786, 43; 



FAMILY VII. SPIRILLACEAE 



255 



Winter, in Rabenhorst's Kryptogamen- 
Flora, ;, Die Pilze, 1884, 63.) 

ser'pens. L. v. serpo to crawl or creep; L. 
part. adj. serpens creeping. 

Long, curved rods with two (o three wave- 
like undulation.s, 0.8 to 1.0 micron in di- 
ameter; wave length, 8 to 9 micron.s. Width 
of spiral, 1.5 to 1.8 microns. Volutin granules 
in cytoplasm. Motile, possessing tufts of 
fiagella at both poles. Gram-negative. 

Gelatin colonies: Yellowish to brownish, 
granular, entire. 

Gelatin stab: Yellowish surface growth. 
Slow liquefaction. 

Agar colonies: Heavy cream-colored 
growth. 

Agar slant: Grayish, with yellowish 
center, granular, entire. 

Broth: Turbid. 

Litmus milk: Unchanged. 

Potato: Clear orange-yellow growth. 

Indole not produced. 

Catalase-positive. 

Nitrites not produced from nitrates. 

Aerobic, facultative. 

Optimum temperature, 35° C. 

Habitat: Stagnant water. 

3. Spirillum itersonii Giesberger, 1936. 
(Inaug. Diss., Utrecht, 1936, 46 and 57.) 

i.ter.so'ni.i. M.L. gen. noun itersonii of 
Iterson; named for G. van Iterson, a Dutch 
bacteriologist. 

The smallest of the spirilla isolated from 
water. First observed by van Iterson (Proc. 
Kon. Akad. v. Wetensch. Amsterdam, 5, 
1902, 685). 

Small spirals, 0.5 micron in diameter. 
Wave length, 3 to 3.5 microns. Spiral width, 
1 to 1.5 microns. Motile by means of bipolar 
tufts of fiagella. Gram-negative. 

Gelatin stab: No liquefaction. 

Grows readily on peptone agar. White 
colonies becoming brownish black and 
slightly wrinkled. 

Potato: Brownish orange growth. 

Acid from glucose, fructose, ethyl alcohol, 
n -propyl alcohol, n-butyl alcohol and 
glj'cerol. Utilizes acetic, propionic, n-bu- 
tyric, tartaric, fumaric, lactic, citric and 
succinic acids. 



Grows well in pe])tone broth. Also utilizes 
ammonium compounds. 

Catalase-positive. 

Anaerobic growth in the presence of 
nitrates when organic or ammonia nitrogen 
is also available. 

Optimum temperature, 30° C. 

Source: Isolated from water. 

Habitat: Water. 

4. Spirillum tenue Khrenberg, 1838. 
(Die Infusionsthierchen als vollkommende 
Organismen. Leipzig, 1838; also see Bon- 
hoff. Arch. f. Hyg., 26, 1896, 162.) 

te'nu.e. L. adj. tenuis thin. 

Slender spirals 0.7 micron in diameter. 
Wave lengths, 4.5 to 5.0 microns; width of 
wave, 1.5 to 1.8 microns. Activel}' motile in 
peptone water by means of tufts of fiagella 
at each pole. Volutin granules present. 
Gram-negative. 

Gelatin stab: No liquefaction. 

Agar colonies: White, smooth. 

Peptone agar slant: Heavy growth. 

Potato: Light brown growth. 

Acid from glucose and fructose. Slight 
acid from several other sugars and glycerols. 
Utilizes salts of acetic, propionic, n-butyric, 
tartaric, lactic, citric, malic and succinic 
acids. 

Ammonia compounds are used as a source 
of nitrogen. 

Catalase-positive. 

Optimum temperature, 30° C. 

Source: Isolated from putrefying vege- 
table matter. 

Habitat: Putrefying materials. 

5. Spirillum virginianum Dimitroff, 
1926. (Jour. Bact., 12, 1926, 19.) 

vir.gi.ni.a'num. M.L. adj. virginianus 
Virginian; named for the State of Virginia. 

Spirals consisting of )^ to 3 complete 
turns in young cultures, older cultures show- 
ing 7 turns; 0.6 to 0.9 by 3 to 11 microns. No 
volutin granules observed (Giesberger, 
Inaug. Diss., Delft, 1936, 60). Motile by 
means of a single, polar flagellum on one or 
both ends. Gram-negative. 

Gelatin colonies: Entire, conve.x, circular, 
moist, colorless. 



256 



ORDER I. PSEUDOMONADALES 



Gelatin stab: Growth along entire stab. 
No liquefaction (Dimitroff, op. cit., 12, 
1926, 31). Active liquefaction (Giesberger, 
op. cit., 1936, 65). 

Agar colonies: Dew drop, convex, entire, 
moist, colorless. 

Agar slant: Dew drop, isolated colonies. 

Broth: Cloudy, no flocculation. 

Uschinsky's protein-free medium: Abun- 
dant growth. 

Litmus milk: No growth. 

Loeffler's blood serum: Convex, isolated 
dew drop colonies. No liquefaction. 

Potato: No growth. 

Methyl red negative; acetylmethylcar- 
binol not produced. 

Indole not produced. 

Hydrogen sulfide not produced. 

No acid or gas from carbohydrates. 

Lactates and citrates utilized (Giesberger, 
loc. cit.). 

Nitrites not produced from nitrates. 

Aerobic, facultative. 

Optimum temperature, 35° C. 

Source: Isolated from mud on an oyster 
shell. 

Habitat: Probably the muddy bottom of 
brackish water. 

6. Spirillum minus Carter, 1888. (Car- 
ter, Sci. Mem. Med. Officers Army India, 3, 
1888, 45; Spirochaeta muris Wenyon, Jour. 
Hyg., 6, 1906, 580.) 

mi'nus. L. comp.adj. minus less, smaller. 

Description taken from Adachi (Jour. 
Exp. Med., S3, 1921, 647) and Giesberger 
(Inaug. Diss., Delft, 1936, 67). 

Short thick cells, 0.5 by 3.0 microns, 
having 2 or 3 windings which are thick, 
regular and spiral. Actively motile by means 
of bipolar tufts of flagella. Gram-negative. 

Has not been cultivated on artificial 
media. 

Aerobic, facultative. 

Pathogenic for man, monkeys, rats, mice 
and guinea pigs. 

This species is regarded by some as a 
spirochaete. Because of its habitat and 
wide distribution it has been described 
under many different names. It is possible 
that some of these names indicate varieties 
or even separate species. See Beeson (Jour. 



Amer. Med. Assoc, 123, 1943, 332) for im- 
portant literature. 

Source: Found in the blood of rats and 
mice. 

Habitat: A cause of rat-bite fever. Widely 
distributed. 

7. Spirillum kutscheri Migula, 1900. 
{Spirillum undula majus Kutscher, Cent. f. 
Bakt., I Abt., 18, 1895, 614; Migula, Syst. d. 
Bakt., 2, 1900, 1024.) 

ku'tsche.ri. M.L. gen. noun kutscheri of 
Kutscher; named for K. H. Kutscher, the 
German bacteriologist who first isolated 
this organism. 

Stout, spiral -shaped threads 1.5 microns 
in diameter. Wave lengths, 10.5 to 12.5 mi- 
crons; width, 3.0 to 4.5 microns. The spiral 
form may be lost on continued cultivation. 
Volutin granules present. Motile by means 
of tufts of flagella at the poles. Gram-nega- 
tive. 

Gelatin plate: Surface colonies are trans- 
parent and round; deep colonies are dark 
brown. 

Gelatin stab: Slow liquefaction. 

Agar colonies grow poorly; granular. 
Deep colonies yellowish green to dark 
brown. 

Agar slant: Delicate, transparent growth. 

Potato: Limited growth. 

Utilizes malic and succinic acids. 

Grows well on peptone broth. Also 
utilizes ammonia compounds. 

Catalase-positive. 

Optimum temperature, between 22° and 
27° C. 

Source: Isolated from putrid materials 
and liquid manure. 

Habitat: Putrefying liquids. 

8. Spirillum volutans Ehrenberg, 1832. 
(Prototype, Vibrio spirillum Miiller, Ani- 
malcula infusoria et marina, 1786; Ehren- 
berg, Physik. Abhandlungen d. k. Akad. 
Berlin, 1832, 38.) 

vo'lu.tans. L. v. voluto to tumble about; 
L. part. adj. volutans tumbling about. 

The largest of the spirilla; probably first 
seen by Miiller. 

Spiral-shaped cells 1.5 microns in di- 
ameter. Wave length, 13 to 14 microns; 



FAMILY VII. SPIRILLACEAE 



257 



width 4 to 5 microns. Slightly attenuated 
ends. Dark granules of volutin are present 
in the cytoplasm. Motile, possessing a tuft 
of ten to fifteen fiagella at each pole. Gram- 
negative. 

Migula (Syst. d. Bakt., 2, 1900, 1025) 
reports that this species has not been 
cultivated on artificial media and that the 
cultures described by Kutscher (Ztschr. f. 
Hyg., 20, 1895, 58) as Spirillum volutans 
are of a different species. Vahle (Cent. f. 
Hakt., II Abt., 25, 1910, 237) later describes 
the cultural characters of an organism which 
he regards as identical with Kutscher's 
organism. Giesberger (Inaug. Diss., Delft, 
1936, 65) saw what he felt was the true 
Spirillum volutans but could not cultivate 
it. 

Optimum temperature, 35° C. 

Habitat: Stagnant water. 

9. Spirillum lipoferum Beijerinck, 1925. 
(Azotobacier spirillum Beijerinck, Kon. 
Akad. Wetensch. Amsterdam, 30, 1923, 431, 
([uoted from Giesberger, Inaug. Diss., 
Delft., 1936, 24; Beijerinck, Cent. f. Bakt., 
II Abt., 63, 1925, 353.) 



li.po'fe.rum. Gr. noun lipus fat; L. v.fero 
to carry; M.L. adj. lipoferus fat-bearing. 

Curved cells with one-half to one spiral 
turn. Contain minute fat droplets which 
ma}^ deform the cells. Motile by means of a 
tuft of polar fiagella. Gram-negative. 

Calcium malate agar colonies: Circular, 
small, transparent, dry. The malate is oxi- 
dized to calcium carbonate. Cells contain 
fat droplets. 

Peptone agar colonies: More abundant 
development. Cells lack fat droplets and 
are typically spirillum in form. 

Glucose peptone broth: Cells actively 
motile with large fat droplets. 

Fixes atmospheric nitrogen in partially 
pure cultures, i.e., free from Azotobacter 
and Clostridium (Beijerinck, loc. cit.). 
Schroder (Cent. f. Bakt., II Abt., 85, 1932, 
17) failed to find fixation of nitrogen when 
she used cultures derived from a single cell. 

Aerobic. 

Optimum temperature, 22° C. 

Beijerinck regards this as a transitional 
form between Spirillum and Azotobacter. 
Giesberger (op. cit., 1936, 64) thinks it a 
Vibrio. 

Habitat: Garden soil. 



Genus VIII. Paraspirillum Dobell, 1912.* 
(Arch. f. Protistenk., 2^, 1912, 97.) 

Pa.ra.spi.ril'lum. Gr. pref. para beside; M.L. neut.n. Spirillum a genus of bacteria; 
M.L. neut.n. Paraspirillum Spirillum-like (organisms). 

Cells spiral or S-shaped, tapering toward the ends, wdth a well marked thickening toward 
the middle of the body; resemble much elongated and spirally twisted spindles. Motile by 
means of a single, polar flagellum. Found in fresh water. 

Dobell {loc. cit.) believes that this organism belongs to the Spirillaceae rather than to the 
Spirochaetaceae . 

The type species is Paraspirillum vejdovskii Dobell. 



1. Paraspirillum vejdovskii Dobell, 
1912. (Arch. f. Protistenk., 24, 1912, 97.) 

vej .dov'ski.i. M.L. gen. noun vejdovskii of 
Vejdovsky; named for Prof. F. Vejdovsky. 

Spiral or S-shaped rods, tapering toward 
the ends, 8 to 25 microns in length, averag- 
ing 15 microns. Width, in the middle, 1.5 to 
to 2.0 microns. A definite spherical to ellip- 
soidal nucleus is present. The cytoplasm 
immediately about the nucleus is hyaline 



or very finely granular. Volutin granules 
are numerous between the hyaline area and 
the ends of the cell. Locomotion is screw- 
like, resembling that characteristic of spe- 
cies of Spirillum. The motion is reversible, 
and cells may swim in either direction. In 
motion the cell seems to be rigid, but it may 
increase or decrease the amount of bending. 
Sometimes the cell is much-curved, at other 



Prepared by Prof. R. E. Buchanan, Iowa State College, Ames, Iowa, July, 1952. 



258 ORDER I. PSEUDOMONADALES 

times it is almost straight. A single, polar This organism has not been cultivated, 

flagellum is demonstrable; such a flagellum Source: Encountered only once in a cul- 

may occur at each end. Division of the cell ture of Oscillatoriae in water from the River 

is transverse and is preceded by a division Granta near Cambridge, England, 
of the nucleus. Habitat: Fresh water. 

Genus IX. Selenonionas von Prowazek, 1913* 

(Von Prowazek, Cent. f. Bakt., I Abt., Orig., 70, 1913 (July), 36; Selenomastix 
Woodcock and Lapage, Quart. Jour. Micro. Sci., S9 (N.S.), 1913 (November), 433.) 

Se.le.no. mo'nas. Gr. noun selene the moon; Gr. noun monas a unit, monad; IM.L. fem.n. 
moon monad. 

Cells kidney- to crescent-shaped with blunt ends. Motile by means of a tuft of flagella 
attached to the middle of the concave side. The flagella are thicker at the base than at the 
free end and are usually about one and a half times as long as the cell. Gram-negative. 
Anaerobic. Parasites found in the alimentary tracts of mammals, including man. 

Three species are described, and it is possible that when comparative studies are made 
the three will be found to belong to but a single species. On the other hand it is equally pos- 
sible that not only these three but also additional species will be recognized (Lessel and 
Breed, Bact. Rev., 18, 1954, 167). 

The type species is Selenomonas palpitans Simons. 

Key to the species of genus Selenonionas. 

I. Found in the coeca of guinea pigs. 

1. Selenonionas palpitans. 
II. Found in the human mouth cavity. 

2. Selenonionas sputigena. 
III. Found in the rumen juices of ruminants. 

3. Selenomonas ruminantiuni . 

1. Selenomonas palpitans Simons, 1922. a true nucleus, dividing as the cell divides. 

(Guinea pig selenomonad, da Cunha, Brasil Boskamp {ibid., 65) was unable to deter- 

Medico, 29, 1915, 33; Selenomonas palpitans mine whether this division was mitotic or 

Simons {nomen dubium), Cent. f. Bakt., I amitotic. With Giemsa's stain the cyto- 

Abt., Orig., 57, 1921, 50; Simons, inBoskamp, plasm is blue whereas the chromatin ma- 

ibid., 88, 1922, 58.) terial, the cell membrane and the flagella 

pal 'pi. tans. L. part. adj. palpitans trem- stain red. Gram-negative, 

bling. Anaerobic (?) as presumed by Boskamp 

Description taken from Boskamp {loc. (^^^^^ ^^^^^ fron^ the fact that these 

f^'^i-)- organisms, in feces, died quickly when 

Kidney- to crescent-shaped cells with ^^^^^^^ ^^ ^j^. ^.j^^^ likewise did not grow 

blunt ends, 1.8 to 2.3 by 6.8 to 9.1 microns. ,. „ „ j-v.^^ , ^^^;„ 

' . / ,^ , a ^^ ^u aerobically on ordmary media. 

Motile by means of a tuft of flagella on the ., t^ j • xi_ c 

•' . . . ^, ,1 rru a 11 Source: Found in the cecum oi a guinea 
concave side of the cell. The flagella are 

thicker at the base than at the free end and P*^ 



are 



usually about one to one and a half times 



Habitat : Found in the ceca of guinea pigs. 



long as the cell. A highly refractive Not found in the buccal cavity, the stomach 

granule is found on the concave side at the or the small intestine. Decrease rapidly in 

base of the tuft of flagella; this granule number in the upper large intestine and dis- 

stains with nuclear stains and appears to be appear entirely in the lower part. 

* Prepared by Mr. Erwin F. Lessel, Jr., Cornell University, Geneva, New York, January, 
1954. 



FAMILY VII. SPIRILLACEAE 



259 



2. Selenonionas sputigena (Fliigge, 
1886, emend. Muhlens, 1909) Dobell, 1932. 
(Spirillum sputigenum Fliigge, Die Mikro- 
organismen, 2 Aufl., 1886, 387; Muhlens, 
Cent. f. Bakt., I Abt., Orig., 48, 1909, 524; 
Selenomonas sputigena Boskamp (nomen 
provisorium) , Cent. f. Bakt., I Abt., Orig., 
88, 1922, 70; Dobell, Antony van Leeuwen- 
hoek and His "Little Animals". New York, 
1932, 239, plate XXIV, and 245, footnote 2; 
Vibrio sputigenus Pr^vot, Man. de Classif. 
des Bact. Anaer., Paris, 1« ed., 1940, 85; not 
Vibrio sputigenus Bergey et al., Manual, 
1st ed., 1923, 80.) 

spu.ti'ge.na. L. noun sputum spit, spu- 
tum; L. V. gigno to produce; M.L. adj. 
sputigenus sputum-produced. 

Description taken from Muhlens (op. cit., 
1909, 524). Also see Hoffmann and von Pro- 
wazek (Cent. f. Bakt., I Abt., Orig., 4i , 
1906, 820), von Prowazek (ibid., 70, 1913, 36) 
and Macdonald (Thesis, Univ. of Toronto, 
1953,95 pp.). 

Comma- and crescent-shaped cells, 
thicker and longer than the cholera vibrio, 
occasionally occurring in pairs in the form 
of an S. Motility is vibratory, rotating, 
whirling and boring in nature. Dobell (op. 
cit., 1932, 245) feels that the type of motility 
depicted in Leeuwenhoek's drawing (ibid., 
239, plate XXIV, Fig. B, with motion shown 
in C to D) is so characteristic of Spirillum 
sputigenum that the organism labelled Fig. 
B by Leeuwenhoek is, in all probability. 
Spirillum sputigenum Miller. Hoffmann and 
von Prowazek {op. cit., 1906, 820) describe 
this organism as a crescent-shaped rod with 
a thick flagellum that appears to be attached 
on the concave side. Muhlens {op. cit., 1909, 
525) reports 1 to 3 flagella, the majority of 
the organisms having a single thick flagel- 
lum (a tuft of flagella) on the concave side. 
Von Prowazek {op. cit., 1913, 36) later shows 
excellent figures of these thick flagella 
treated with Giemsa's stain. These figures 
show that the thick flagellum is really a tuft 
of flagella which may separate like the 
bristles of a paint brush. Stains pale red 
with Giemsa's stain. 

Horse-serum agar stab: Fine, hazy 
colonies develop in the low portions. Growth 
begins in 1 to 3 days as fine, cloudy colonies 
with somewhat thicker, yellowish centers 



and increases to a thick streak, opaque in 
the center and cloudy-transparent at the 
edges. 

Kutscher's placenta agar: Good growth. 
Anaerobic growth in the lower two-thirds 
of stab and shake cultures. No visible gas 
produced. 

Serum broth: No growth. 

The following characters are from Mac- 
donald {op. cit. 1953) : 

Blood agar: Growth occurred only when 
plates were reduced immediately after 
streaking. Colonies were smooth, convex, 
grayish yellow, and less than 0.5 mm in 
diameter. 

Difco thioglycollate broth: Growth heavy 
and granular in 48 hrs. The best fluid me- 
dium in which to maintain cultures. 

Difco thioglj'coUate agar shake cultures: 
Irregularly shaped, yellow colonies. 

Litmus milk: Acid and coagulated. 

Acid from glucose and sucrose. Slight 
acid from mannitol. 

Indole not produced. 

Hydrogen sulfide not produced. 

Nitrites produced from nitrates. 

Optimum temperature, 37°C. Growth 
range, from 20° to 45° C. The pH range for 
growth is 4.5 to 8.6 with the best growth 
between 5.5 and 8.6. 

Not pathogenic for guinea pigs injected 
subcutaneously or intracardially, nor for 
mice injected intraperitoneally. 

Distinctive characters: Early investiga- 
tors described an organism of this type but 
were unable to culture it, e.g. Lewis (Lancet, 
Sept. 20, 1884, who regarded the organism 
he found as identical with the cholera 
vibrio) and Miller (The Microorganisms of 
the Human Mouth, Philadelphia, 1890, 75) ; 
Miller also gives an excellent discussion of 
the early work. Muhlens {op. cit., 1909, 526) 
described a variety of this species with 
smaller cells. 

While Macdonald describes this species 
as peritrichous, he reports (personal com- 
munication) that others have felt that his 
electron micrographs could be interpreted 
as showing a cluster of flagella attached at 
the middle of the concave side of the cres- 
cent-shaped cells, and that in dark field 
examination he observed, as had earlier 
workers, a single heavy flagellum attached 



260 



ORDER I. PSEUDOMONADALES 



at the middle of the concavity. The so-called 
nuclear body shows plainly in the electron 
micrographs. 

Source: Isolated from the buccal cavity of 
man. 

Habitat: Found in the buccal cavity. 

3. Selenoinonas runiinantium (Certes, 
1889) Wenyon, 1926. {Ancyromonas runiinan- 
tium Certes, Bull. Soc. Zool., France, H, 
1889, 70; Selenomastix ruminantium Wood- 
cock and Lapage, Quart. Jour. Micro. Sci., 
59 (N.S.), 1913-1914, 433; Wenyon, Proto- 
zoology. 1, 1926,311.) 

ru.mi.nan'ti.um. L. part. adj. ruminans, 
ruminantis ruminating; M.L. neut.pl.n. 
ruminantia ruminants; M.L. pi. gen. noun 
ruminantium of ruminants. 

Rigid, crescent-shaped cells which meas- 
ure 2 to 3 by 9.5 to 11 microns. Woodcock and 
Lapage {op. cit., 434) state that the cells are 
only slightly crescentic and never assume 
the S shape as reported by Certes (op. cit., 
439); furthermore, they report that the 
curve lies in but one plane. A tuft of flagella 
which attains a length of 8.0 to 9.5 microns 
springs from the center of the concavity. 
The protoplasm stains homogeneously ex- 
cept at the base of the flagella where a 



deepl}^ staining mass is easily demonstrable. 
Reproduction is by binary fission transverse 
to the long axis of the cell and through the 
flagellar region. Each half of the flagella 
passes to one of the two pear-shaped daugh- 
ter cells where it is attached near the blunt 
end; later the flagella undergo an apparent 
shift in position to the center of the con- 
cavity. 

Probably anaerobic but does not grow on 
ordinary media either aerobically or an- 
aerobically. 

Woodcock and Lapage (op. cit., 445 ff.) 
found ellipsoidal, non-motile organisms 
mixed abundantly with the motile crescents 
and felt that these might represent a stage in 
the life history of the crescents although 
they could not demonstrate this. Wenyon 
{op. cit., 311) also thinks that a rounded 
flagellate organism may be a stage of the 
crescent-shaped organism, but he presents 
no proof to support this conclusion. 

Source: Found by Certes {op. cit., 70) by 
microscopical examination of rumen juice 
of cattle, sheep and deer. Later found by 
Woodcock and Lapage {op. cit., 433) very 
abundantly in the rumen juice of goats. 

Habitat : Found as a predominant organ- 
ism on microscopical examination of rumen 
juices from herbivorous mammals. 



Genus X. Myconostoc Cohn, 1875.* 
(Beitrage z. Biol. d. Pflanzen, 1, Heft 3, 1875, 183.) 

My.co.nos'toc. Gr. noun myces fungus; M.L. neut.n. Nostoc a genus of algae; i\LL. neut.n. 
Myconostoc fungus nostoc. 

Curved, colorless cells occurring singly or in curved or spiral chains. Embedded in small, 
spherical, gelatinous masses. Found in fresh- or sulfur-water containing decomoosine 
organic matter. 

The type species is Myconostoc gregarium Cohn. 



1. Myconostoc gregarium Cohn, 1875. 
(Cohn, Beitrage z. Biol. d. Pflanzen, 1, 
Heft 3, 1875,_ 183; Spirosoma gregarium 
Migula, Syst. d. Bakt., ^, 1900, 960.) 

gre.gar'i.um. L. adj. gregarius of or be- 
longing to a flock or group. 

Cells curved to comma-shaped, 1 by 5 to 
10 microns, often joined together as spiral 
chains which may resemble horse-shoes or 
which may twist around each other to form 



coiled, non-septate, non-motile, colorless 
filaments. The filaments are usually en- 
closed in a spherical, solid, microscopic, 
gelatinous mass which measures 10 to 17 
microns in diameter; these masses may 
clump together and form a cluster, usually 
on the surface of the water, which is visible 
to the naked eye. Excellent illustrations de- 
picting the nature of this species are shown 
in Zopf (Die Spaltpilze, 3 Aufl., 1885, 23). 



* Prepared by Mr. Erwin F. Lessel, Jr., Cornell University, Ithaca, New York. Septem- 
ber, 1953. 



FAMILY VII. SPIRILLACEAE 



261 



When the gelatinous mass disintegrates, 
swarm cells are formed which are pre- 
sumably polar flagellate. The individual 
cells are granular and stain rather poorly. 
During reproduction, the filaments be- 
come somewhat elongated and expand the 
gelatinous mass to an ellipsoidal shape. As 
the gelatinous sphere undergoes transverse 
fission, there is a concomitant division of the 
filament, the daughter cells finally separat- 
ing from each other. Lankester (Quart. 
Jour. Micros. Sci., 13, (N.S.), 1873, 408) 
erroneously believed this gelatinous form 



to be a stage in the life cycle of a Spii-ilhim, 
probably Spirillum undula Ehrenberg. 

These organisms have not been cultivated 
on artificial media. 

Source : Found in the surface scum of sul- 
fur-water in a jar with decomposing algae, 
especially Spirogyra sp. (Cohn, op. cit., 
1875, 183). Also found by Migula {op. cit., 
1900, 960) in peat bogs between Weingarten 
and Karlsruhe. Hansgirg (Osterr. Vot. 
Ztschr., 38, 1888, 265) frequently found this 
organism among his algal cultures in Bo- 
hemia. 

Habitat: Fresh-water ponds. 



ORDER II. CHLAMYDOBACTERIALES BUCHANAN, 1917.* 



(Buchanan, Jour. Bact., 2, 1917, 162.) 

Chla.my.do.bac.te.ri.a'les. M.L. fern. pi. n. Chlamdobacteriaceae type family of the order 
Chlamydobacteriales ; -ales ending to denote an order ; M.L. fern. pi. n. Chlamydobacteriales the 
Chlam ydobacteriaceae order . 

Colorless, alga-like bacteria which occur in trichomes. May or may not be ensheathed. 
They may be unbranched or may show false branching. False branching arises from a lateral 
displacement of the cells of the trichome within the sheath; this gives rise to a new trichome 
so that the sheath is branched while the trichomes are separate. The sheaths may be com- 
posed of an organic matrix impregnated with iron or manganese oxides, or they may be 
composed of an organic matrix free from these oxides. Gram-negative. Reproduction may be 
by flagellate swarm spores or by non-motile conidia. Endospores of the type found in Bacil- 
lus are never developed. Fresh-water and marine forms. 

Key to the families of order Chlamydobacteriales. 

I. Conidia, when formed, are motile by means of a sub-polar tuft of flagella. 

A. Possesses trichomes in which false branching may occur. Motile swarm cells may be 
formed. 

Family I. Chlamydobacteriaceae . p. 262. 

B. Possesses ensheathed, unbranching trichomes which may be very long (0.5 cm). 
Found in fresh water. 

Family II. Peloplocaceae, p. 270. 
II. Non-motile conidia are produced. 

Family III. Crenotrichaceae, p. 272. 



FAMILY I. CHLAMYDOBACTERIACEAE MIGULA, 1894. 
(Arb. bakt. Inst. Hochschule, Karlsruhe, 1, 1894, 237.) 

Chla.my.do.bac.te.ri.a'ce.ae. Gr. noun chlamys, chlamydis a cloak; Gr. neut.n. bac- 
terium a small rod; -aceae ending to denote a family; M.L. fem.pl.n. CJdaui ydobacteriaceae 
the family of the sheathed bacteria. 

Bacteria which occur in trichomes and which frequently show false branching. Sheaths, 
when present, may or may not be impregnated with ferric and/or manganese oxides. Cells 
divide transversely. Swarm cells, if developed, are usually motile by means of a tuft of 
flagella. Usually found in fresh water. 

Key to the genera of family Chlamydobacteriaceae. 

I. Trichomes surrounded by sheaths which are usually not impregnated with iron or 
manganese oxides and which do not dissolve in hydrochloric acid. Large forms, mostl}^ 
sessile. 

* Rearranged and revised by Prof. Robert S. Breed, Cornell University, Geneva, New 
York, November, 1953; further revision, with the introduction of an additional family and 
genera and species, by Prof. Dr. Herbert Beger, Institut fiir Wasser-, Boden- und Luft- 
hygiene, Berlin-Dahlem, Germany, January, 1955. 

262 



FAMILY I. CHLAMYDOBACTERIACEAE 263 

Genus I. Sphaerotilus, p. 263. 
II. Trichomes surrounded by sheaths impregnated with oxides of iron or manganese which 
dissolve in strong h.ydrochloric acid. Free-living or sessile. 

A. Individual trichomes, each with a sheath. 

Genus II. Leptothrix, p. 264. 

B. Sheaths contain more than one trichome; the trichomes are sometimes in a fan-like 
arrangement. 

Genus III. Toxothrix, p. 269. 

Genus I. Sphaerotilus Kiitzing, 1833. 

(Kiitzing, Linnaea, 8, 1833, 385; Cladothrix Cohn, Beitr. z. Biol. d. 
Pflanz., 1, Hefts, 1875, 185.) 

Sphae.ro'ti.lus. Gr. noun sphaera a sphere; Gr. noun tilus anything shredded, flock, 
down; M.L. mas.n. Sphaerotilus sphere down. 

Attached or free-floating, colorless trichomes showing false branching, though this may 
be rare in some species. When e.xamined under the electron microscope, the sheath shows a 
homogeneous structure. Sheath may become j'ellowish or brown with the deposition of iron 
oxide. The deposition of iron is dependent on environmental factors, not on the ph3'siologi- 
cal ability to store iron. Trichomes consist of rod-shaped or ellipsoidal cells surrounded by 
a firm sheath. Multiplication occurs both by non-motile conidia and by motile swarm cells, 
the latter with a subpolar tuft of flagella. Gram-negative so far as known. Found in fresh 
water. 

The systematic positions of the species placed in Sphaerotilus, Leptothrix and related ge- 
nera are uncertain. Pringsheim (Phil. Trans. Roy. Soc. London, Series B, 233, 1949, 605, 
and Biol. Reviews, 24, 1949, 200) would combine some of the species now placed in Lepto- 
thrix with Sphaerotilus nutans and broaden the definition of Sphaerotilus to include other 
species here placed in Leptothrix and Clonothrix. However, Beger and Bringmann (Zent. f. 
Bakt., II Abt., 107, 1953, 318) indicate differences in the structures of the sheaths of Sphaero- 
tilus and Leptothrix and give other reasons why it may be better to keep the earlier groupings 
as they have been. 

The type species is Sphaerotilus natui^s Kiitzing. 

1. Sphaerotilus natans Kiitzing, 1833. nitrogen, does not grow in the ordinary pep- 

(Kiitzing, Linnaea, 8, 1833, 385; not (Sp/jae?o- tone solution, grows best with low concen- 

tilus natans Sack, Cent. f. Bakt., II Abt., trations of meat extract (Zikes, Cent. f. 

65, 1925, 116.) Bakt., II Abt., 4S, 1915, 529). See Stokes 

na'tans. L. part. adj. wafa/is swimming. (Jour. Bact., 67, 1954, 278) for a recent study 

Colorless, slimy trichomes which attain of the cultural and physiological charac- 

a length of several millimeters. The tri- teristics of this species, 

chomes are ensheathed, show false branching Distinctive characters: This species 

and are either free-floating or attached at thrives in great tassels on solid substrata 

one end by means of a small disc. The indi- covered by dirty running water. These tas- 

vidual cells are cylindrical, 1 by 2 to 6 mi- sels are composed of trichomes of bacterial 

crons, and vacuolated (Lackey and Wattie, cells held together by slim}^, tubular 

U. S. Pub. Health Ser., Pub. Health Repts., sheaths. The latter maj' become softened 

55,1940,975). and dissolved, releasing Pseudomonas-hke 

]\Iultiplication occurs through the forma- swarm cells. The same organism grows in 

tion of conidia within the sheath of the a quite different state in quiet waters 

vegetative cells, from which thej' swarm out with only a little organic matter, forming 

at one end, swim about for a time, then branched structures occurring in trichomes, 

attach themselves to objects and develop the sheaths of which are not slimy. A third 

into delicate trichomes. form is produced when ferrous compounds 

Gelatin rapidly liquefied, requires organic and very little organic substance are pres- 



264 



ORDER II. CHLAMYDOBACTERIALES 



ent. The sheaths become brittle and glass- 
like in appearance by deposition of ferric 
hj^droxide in a hard colloidal form. Prings- 
heim (Endeavour, 11, 1952, 209) states that 
under these conditions it is identical with 
Leptothrix ochracea, which looks ochre-like 
in bulk but never brown under the micro- 
scope. 

Source: Originally found in polluted 
waters. May become a real nuisance in 
sewage purification plants of the activated 
sludge type (Lackey and Wattie, op. cit., 
1940, 975) and in streams polluted with sul- 
fite liquor from pulp and paper mills 
(Lackey, Mimeographed Rept., U. S. 
Pub. Health Ser., 1941). 

Habitat: Stagnant and running water, 
especially sewage-polluted streams. Widely 
distributed throughout the world in fresh 
water. 

2. Sphaerotilus dichotonius (Cohn, 
1875) Migula, 1900. (Cladothrix dichotoma 
Cohn, Beitr. z. Biol. d. Pflanz., 1, Heft 3, 
1875, 185; Migula, Syst. d. Bakt., 2, 1900, 
1033.) 

di.cho'to.mus. Gr. adj. dichotomus di- 
vided, forked. 

The identity of this species as distinct 
from Sphaerotilus natans has been ques- 
tioned. In his text, Cohn reports the di- 
ameter of the trichomes to be 0.3 micron. 
This clearly is an error as his figures at 



600X show the diameter of the trichomes to 
be greater than the diameter of Bacillus 
anthracis spores shown at the same mag- 
nification. Such spores are 1.3 to 1.5 microns 
in diameter. 

Zikes (Cent. f. Bakt., II Abt., 43, 1915, 
529) gives the following differential charac- 
ters : Cells smaller than those of Sphaerotilus 
natans, 1.5 to 2.5 microns; false branching 
constant; grows best in high concentrations 
of meat extract; will grow in ordinary pep- 
tone solutions; can utilize inorganic nitro- 
gen; liquefies gelatin slowly. 

Source: Isolated by Cohn from water con- 
taining Myconostoc. 

Habitat: Comparatively unpolluted fresh 
water capable of sustaining algae. 

3. Sphaerotilus flviitans (Migula, 1895) 
Schikora, 1899. {Streptothrixfluitans Migula, 
in Engler and Prantl, Die natiirl. Pflanzen- 
fam., 1, la, 1895, 38; Schikora, Ztschr. f. 
Fischerei, 7, 1899, 1-28.) 

flu'i.tans. L. part. adj. fluitans floating. 

Verj thin, attached trichomes as much as 
1 cm in length. The trichomes are sur- 
rounded by a soft sheath from which almost 
spherical conidia issue, usually attaching 
themselves to the exterior of the sheath 
where they multiply. 

Source: Found attached to pieces of wood 
and stems of plants in running water. 

Habitat: Fresh water. 



Genus II. Leptothrix Kiitzing, 1843. 

(Kiitzing, Phycologia Generalis, 1843, 198; not Leptotrichia Trevisan, Reale 
1st. Lombardo di Sci. e Lettere, Ser. 2, 12, 1879, 138.) 

Lep'to.thrix. Gr. adj. leptus fine, small; Gr. noun thrix hair; M.L. fem.n. Leptothrix fine 
hair. 

Trichomes of cylindrical, colorless cells with a sheath at first thin and colorless, later 
thicker, yellow or brown, encrusted with iron or manganese oxide. The oxides may be dis- 
solved by dilute acid, whereupon the inner cells show up well. If the sheath contains man- 
ganese oxide, it does not dissolve completel}^ in weak acids. When examined under the elec- 
tron microscope, the sheath shows an alveolar structure. Multiplication is by cell division 
with individual cells occasionally slipping out of the sheath as reproductive cells. These 
are sometimes motile with a tuft of flagella. False branching may occur. Gram-negative and 
not acid-fast so far as known. Usually found in fresh water. 

The type species is Leptothrix ochracea Kiitzing. 

Key to the species of genus Leptothrix. 

I. Trichomes straight, not spirally twisted. 

A. Trichomes free-floating and unbranched. Sheath thin. 



FAMILY I. CHLAMYDOBACTERIACEAE 265 

1. Trichomes 1 to 3 microns thick. 

1. Lcplothrix ochrncea. 

2. Trichomes 0.4 to 0.5 micron thick. 

2. Leptothrix thermnlis. 
B. Trichomes attached. 

1. Attachment is by means of a hoklfast. 

a. Trichomes arise singly, each from its own holdfast. 

b. Sheath very thin, encrusted only at the base of the trichome. 

3. Leptothrix sideropons. 
bb. Sheaths thick. 

c. Trichomes showing no or only a few false branches. Cells up to 1 
micron thick. 

4. Leptothrix discophora . 

cc. Trichomes always with numerous false branches. Cells 1.4 microns 
thick. 

5. Leptothrix major. 

aa. Numerous trichomes arising from a common holdfast. 

b. Sheaths not tapering to the tip. Trichomes form sessile, hemispherical 
clusters. 

6. Leptothrix lopholea. 

bb. Sheaths tapering to the tip. Trichomes usually form free-living colonies 
in which the trichomes radiate like the spokes of a wheel. 

7. Leptothrix echinata. 

2. Attached by gelatinous masses. 

8. Leptothrix epiphytica. 

II. Trichomes spirally twisted (except in a variety of Leptothrix pseudovacuolata). 

A. Epiphytic, growing twisted around thread-like algae. 

9. Leptothrix voluhilis. 

B. Free-living in water or on the surface of mud. 

1. Trichomes very thin; sheaths tapering slowly to the tip, ending in a sharp point. 

a. Cells 0.3 micron in diameter. 

10. Leptothrix skujae. 
aa. Cells 0.9 micron in diameter. 

11. Leptothrix winogradskii. 

2. Trichomes thick, sometimes not twisted; sheaths rounded at the tip. 

12. Leptothrix pseudovamwlata. 

1. Leptothrix ochracea (Roth, 1797) rounded by a delicate sheath which later 

Kiitzing, 1843. {Conferva ochracea Roth, becomes yellow to brown in color. Sheath 

Catal. bot. I, 1797, Table V, Fig. 2; also see alveolar, completely dissolving in dilute 

Dillwyn, Syn. Conf., 1802, Table 62; Kiit- hydrochloric acid. When the sheath becomes 

zing, Phycologia generalis, 1843, 198.) very thick, the trichomes slip out of the 

o.chra'ce.a. Gr. noun ochra j-ellow ochre; sheath and secrete a new one so that many 

M.L. adj. ochraceus like ochre. empty sheaths are found. Presumably polar 

Description taken from Kiitzing (loc. cit.) flagellate swarm cells have been observed, 

and Cataldi (Estudio Fisiologico y Siste- Not acid-fast. Gram-negative, 

mdtico de Algunas Chlamydobacteriales. Gelatin: No liquefaction. 

Thesis, University of Buenos Aires, 1939, Iron citrate and ammonium agar colonies: 

58 and 66). Filamentous and spreading, with wavy 

Cells rod-like, colorless, 0.8 to 1.0 micron. edges. 

Motile. Trichomes long, free-floating, never Manganese acetate agar colonies: Fila- 

attached to a substrate, never branching, 1 mentous, not very large, 

micron in thickness. Young trichomes sur- Iron citrate and ammonium agar slant : 



266 



ORDER II. CHLAMYDOBACTERIALES 



Growth very abundant, spreading over the 
entire surface; iridescent. 

Peptone and manganese acetate broth: 
Abundant growth in the form of loose fiakes. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acetylmethylcarbinol not produced. 

Nitrites produced from nitrates. 

Optimum temperature, 28° C. 

Optimum pH, 8.0. 

Aerobic, but growth favored by the pres- 
ence of CO2 . 

Habitat: Found in iron-bearing, fresh 
waters; widely distributed. 

2. Leptothrix thermalis (Molisch, 1925) 
Dorff, 1934. (Chlamydothrix thermalis Mo- 
lisch, Sc. Rept. Tohoku Imp. Univ., 4 ser. 
Biol., Sendae, Japan, 1, 1923, 135 (or pos- 
sibly 1, 1925, 146); Dorff, Die Eisenorganis- 
men, Pflanzenforschung, Heft 16, 1934, 38.) 

ther.ma'lis. Gr. noun therme heat; M.L. 
adj. thermalis pertaining to heat. 

Unbranched trichomes, 0.4 to 0.5 micron 
thick, united in bundles. Surrounded by a 
sheath which may store iron and turn 
brown. 

Source : From warm and hot spring waters 
in Japan. 

Habitat: Found in warm and hot (37° to 
74° C.) spring waters. 

3. Leptothrix sideropous (Molisch, 
1910) Cholodny, 1926. {Chlamydothrix sider- 
opous Molisch, Die Eisenbakterien, 1910, 
14; Cholodny, Die Eisenbakterien, Pflanzen- 
forschung, Heft 4, 1926, 25.) 

si.de'ro.pous. Gr. adj. sideropus or 
sideropous iron-footed. 

Description taken from Molisch {op. cit. 
1910, 14) and Cataldi (Estudio Fisiologico 
y Sistemdtico de Algunas Chlamydobac 
teriales. Thesis, University of Buenos Aires 
1939, 62 and 66). 

Cells rod-shaped, 0.5 to 0.8 micron 
Motile. Trichomes short and unbranched 
Sheath very thin and colorless, giving an 
iron reaction only at the base of the tri 
chome. Attached by a broad holdfast which 
gives a marked iron reaction. Not acid-fast. 
Gram-negative. 

Gelatin: No liquefaction. 



Iron citrate and ammonium agar colonies : 
Very filamentous. Colonies and filaments 
encompassed by a spattering of rust-colored 
spots. 

Manganese acetate agar colonies: Large 
and filamentous, the filaments being 
strongly colored. 

Iron citrate and ammonium agar slant: 
Growth in the form of isolated colonies; 
strongly colored. 

Manganese acetate agar slant: Abundant 
growth which adheres to the medium except 
in those places covered with water of con- 
densation. 

Peptone and manganese acetate broth: 
Firm pellicle with a metallic sheen. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acetylmethylcarbinol not produced. 

Nitrites produced from nitrates. 

Optimum temperature, between 25° and 
28° C. 

Optimum pH, 8.0. 

Aerobic; growth not favored by the pres- 
ence of CO2 . 

Habitat: Found growing on the surfaces 
of objects submerged in water; widely dis- 
tributed. 

4. Leptothrix discophora (Schwers, 
1912) Dorff, 1934. (Megalothrix discophora 
Schwers, Cent. f. Bakt., II Abt., 33, 1912, 
273; Leptothrix crassa Cholodny, Cent. f. 
Bakt., II Abt., 61, 1924, 292; Dorff, Die 
Eisenorganismen, Pflanzenforschung, Heft 
16, 1934, 31.) 

dis.co'pho.ra. Gr. noun discus a disc; Gr. 
adj. phorus bearing; M.L. adj. discophorus 
disc-bearing. 

Description taken from Schwers (op. cit., 
1912, 273) and Cataldi (Estudio Fisiologico 
y Sistemdtico de Algunas Chlamydobac- 
teriales. Thesis, University of Buenos 
Aires, 1939, 60 and 66). 

Cells 0.5 by 0.8 micron. Motile. Tri- 
chomes long, slender, articulated, composed 
of elements of varjdng length showing 
false branching (Cholodny, Cent. f. Bakt., 
II Abt., 61, 1924, 297). Usually attached to 
a submerged substrate, but may be free- 
floating. A sheath, thick (10 to 15 microns) 
at the base, tapering toward the free tip 



FAMILY I. CHLAMYDOBACTERIACEAE 



267 



and heavily impregnated with iron oxide, 
surrounds the trichomes. Reproduction by 
motile swarm cells liberated from the tip 
and also by the emergence of the trichome 
from the sheath, with subsequent breaking 
up into individual, non-motile cells. Not 
acid-fast. Gram-negative. 

Gelatin not liquefied. 

Iron citrate and ammonium agar colonies: 
More or less rounded, with oily inclusions, 
filamentous border. 

Manganese acetate agar colonies: Fila- 
mentous growth, the filaments being rather 
large and showing false branching. 

Iron citrate and ammonium agar slant: 
Growth only in the water of condensation, 
rarely on the slant. 

Peptone and manganese acetate broth: 
Abundant growth in the form of loose flakes. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acetylmethylcarbinol not produced. 

Nitrites produced from nitrates. 

Optimum temperature, between 25° and 
28° C. 

Optimum pH, 8.5. 

Aerobic; growth not favored by the pres- 
ence of CO2 . 

Habitat : Found in fresh water; widely dis- 
tributed. 

5. Leptothrix major Dorff, 1934. (Dorff 
Die Eisenorganismen, Pflanzenforschung, 
Heft 16, 1934, 35; also see Beger and Bring- 
mann,Zent. f.Bakt., IIAbt., 107, 1953,323.) 

ma'jor. L. comp.adj. major larger. 

Trichomes, up to 1 and more cm in length, 
attached by a holdfast, richly branched, 
forming tufts. Trichomes composed of rod- 
like cells, 1.4 by 5 to 10 microns, which con- 
tain small false vacuoles. Giant cells up to 
75 microns in length. Two trichomes may be 
found in the same sheath. The sheath may 
be as much as 12 microns in thickness, taper- 
ing to the tip, storing manganese and iron. 
Resembles the sheath of Leptothrix disco- 
phora but is firmer in texture. Light to dark 
l)rown in color. 

Source: From the Spree River near Berlin. 

Habitat: Found in fresh- water streams. 



6. Leptothrix lopholea Dorff, 1934. (Die 
Eisenorganismen, Pflanzenforschung, Heft 
16, 1934, 33.) 

lo.pho'le.a. Gr. noun lophus a crest; 
M.L. dim. adj. lopholeus somewhat crested 
or tufted. 

Short, slender unbranched trichomes, 
uniform in diameter, attached to a sub- 
strate, 5 to 13 trichomes arising from a 
common holdfast. Trichomes 20 to 33 mi- 
crons long, cells 0.5 by 1.0 to 1.3 microns. 

Sheaths composed of iron oxide; dissolve 
completely in dilute hydrochloric acid. 

Trichomes slip out of the sheath as in 
Leptothrix: ochracea. 

Habitat: Water. 

7. Leptothrix echinata Beger, 1935. 
(Zent. f. Bakt., II Abt., 92, 1935, 401.) 

e.chi.na'ta. Gr. noun echinus the hedge- 
hog; M.L. adj. echinatus like the hedgehog, 
bristly. 

Similar to the preceding species but oc- 
curring in larger colonies, 20 to 50 trichomes 
arising from a common holdfast. Trichomes 
are shorter (9 to 10 microns). 

Sheath is thicker at the base and tapers 
toward the free tip of the trichome, which is 
slightly spiral. The sheath contains an or- 
ganic matrix visible after treatment in di- 
lute hydrochloric acid. 

Habitat: Found in water, especially in 
manganese-bearing waters. 

8. Leptothrix epiphylica (Migula, 1895) 
Schoenichen and Kalberlah, 1900. (Strepto- 
thrix epiphytica Migula, in Engler and 
Prantl, Die natiirl. Pflanzenfam., /, la, 
1895, 36 and 38; Chlamydothrix epiphytica 
Migula, Syst. d. Bakt., 2, 1900, 1033; Schoe- 
nichen and Kalberlah, Eyferth's Einfachste 
Lebensformen, 3rd ed., 1900, 46.) 

e.pi.phy'ti.ca. Gr. prep, epi' upon; Gr. 
noun phytum plant; M.L. adj. epiphyticns 
epiphytic, growing on plants. 

Chains of cells enclosed in short, colorless 
trichomes which are surrounded by thick, 
gelatinous masses; the gelatinous masses are 
attached to algae, but never in groups or 
clusters. 

Habitat: Widely distributed in fresh 
water containing algae. 



268 



ORDER II. CHLAMYDOBACTERIALES 



9. Leptothrix volubilis Cholodny, 1924. 
{Lynghya epiphytica Hieronymus, in Kirch- 
ner, in Engler and Prantl, Die naturl. 
Pflanzenfam., 1, la, 1898, 67; Cholodny, 
Zent. f. Bakt., II Abt., 61, 1924, 292; 
Chlamydothrix epiphytica Naumann, 
Ber. d. deutsch. bot. Gesellsch., 46, 1928, 
141; not Chlamydothrix epiphytica Migula, 
Syst. d. Bakt., 3, 1900, 1033; Leptothrix 
epiphytica Dorff, Die Eisenorganismen, 
Pflanzenforschung, Heft 16, 1934, 32; not 
Leptothrix epiphytica Schoenichen and Kal- 
berlah, Ej'ferth's Einfachste Lebensfor- 
men, 3rd ed., 1900, 46.) 

vo.lu'bi.lis. L. adj. volubilis twisting 
spirally around a support, twining. 

Cells rod-shaped and colorless, measuring 
1 by 2 microns. The cells are enclosed in 
long, cylindrical, unbranched trichomes 
which grow in a spiral fashion around 
threads of Oe(?o^om?/m, Tolypothrix, etc. The 
bacterial trichomes are, in turn, surrounded 
by cjdindrical, ochre-yellow sheaths, about 
3 microns in diameter, which are encrusted 
with iron. The cells m&y leave the sheaths as 
in Leptothrix ochracea. 

Habitat : Found in fresh water containing 
algae. 

10. Leptothrix skujae Beger, 1953. 
{Leptothrix tenuissima Skuja, Symbolae 
Botanicae Upsaliensis, 9, 1948, 33; not 
Leptothrix tenuissima Naegeli, in Kiitzing, 
Species Algarum, 1849, 265; Beger, in Beger 
and Bringmann, Zent. f. Bakt., II Abt., 
107, 1953,331.) 

sku'jae. M.L. gen. noun skujae of Skuja; 
named for H. Skuja, the Swedish algologist 
who first described this species. 

Unattached trichomes, generally without 
false branching, spirally wound together, 
0.3 to 0.4 micron in diameter. The sur- 
rounding sheath is as much as 18 microns in 
diameter and tapers toward the tip. Cells 
rod-shaped and colorless, with a few gran- 
ules lying in chains. 

Resembles Leptothrix discophora Dorff. 

Source: From Store Halsjon, Prov. Upp- 
land, Sweden. Found between other water 
plants and in the plankton. 



Habitat: Found near the shore in lakes. 

11. Leptothrix winogradskii Cataldi, 
1939. (Estudio Fisiologico y Sistemdtico de 
Algunas Chlamydobacteriales. Thesis, Uni- 
versity of Buenos Aires, 1939, 58.) 

wi.no.grad'ski.i. M.L. gen. noun wino- 
gradskii of Winogradsky; named for S. 
Winogradsky, a Russian bacteriologist. 

Cells 0.9 micron in diameter. Motile, 
presumably polar flagellate. Trichomes very 
long, never attached. Sheath 1.5 microns 
thick. Not acid-fast. Gram-negative. 

Gelatin not liquefied. 

Iron citrate and ammonium agar colonies: 
Very filamentous, terminate in spirals, 
lusterless red. 

Manganese acetate agar colonies: Very 
filamentous, red to bright chestnut in color. 

Iron citrate and ammonium agar slant: 
Colonies quite large and distinct, pale 
white. 

Manganese acetate agar slant: Filaments 
long, red to chestnut-colored and inter- 
twined much as are cotton fibers. 

Peptone and manganese acetate broth: 
Filaments quite long and intertwined like 
cotton fibers. 

Indole not produced. 

Hydrogen sulfide not produced. 

Acetylmethylcarbinol not produced. 

Nitrites produced from nitrates. 

Optimum temperature, 37° C. 

Optimum pH, between 5.0 and 9.8. 

Aerobic; growth favored by the presence 
of COo . 

Source: Isolated from fresh water in the 
neighborhood of Buenos Aires. 

Habitat: Presumably widely distributed. 

12. Leptothrix pseudovacuolata (Per- 
filiev, 1925) Dorff, 1934. (Spirothrix pseudo- 
vacuolata Perfiliev, Verh. d. Int. Verein. f. 
theor. u. angew. Limnologie, 1925, Stutt- 
gart, 1927; Dorff, Die Eisenorganismen, 
Pflanzenforschung, Heft 16, 1934, 36.) 

pseu.do. va.cu.o.la'ta. Gr. adj. pseudes 
false; L. adj. vacuus empty; M.L. noun 
vacuola a vacuole; M.L. adj. pseudovacuola- 
tus having false vacuoles. 



FAMILY I. CHLAMYDOBACTERIACEAE 269 

Trichomes, 85 to 250 microns in length, Cells rounded at the ends, thin-walled, 

unbranched, spirally wound, occasionally granular, 1.7 to 2.8 by 3.5 to 30 microns, 
straight. Strongly encrusted with ferric Apparently heterotrophic, 

hydroxide. Spirals 20 to 24 microns from Habitat: Found in bottom muds of deep 

crest to crest. lakes with verj' low oxygen content. 

Genus III. Toxothrix MoUsch, 1925. 

(Molisch, Sci. Rept. Tahoku Imp. Univ., 4 Ser., Biol., 1925, 144; Cryptothrix Perfiliev, Zur 
Mikroflora des Sapropels, Nachrichten des Sapropelkomitees Leningrad, 1, 1922.) 

Tox'o.thrix. Gr. noun toxum a bow; Gr. noun thrix, trichis a thread; M.L. fem.n. Toxo- 
thrix bent thread. 

Trichomes composed of cylindrical, colorless cells with a thin primary sheath; the latter 
soon becomes impregnated with iron oxide. The trichomes lie loosely, longitudinally to- 
gether, in slightly spirally twisted rolls. The continued repetition of this process leads to the 
development of a thick, secondary sheath from which parallel bundles may separate. False 
branching maj^ occur. The sheaths do not completely dissolve in weak acids. Cells may slip 
out of the sheath and may become motile swarm spores. 

The type species is Toxothrix irichogenes (Molisch) Beger. 

Key to the species of genus Toxothrix. 

I. Long, unattached trichomes not in a gelatinous layer. 

1. Toxothrix trichogenes. 
II. Short trichomes lying in a gelatinous layer. 

2. Toxothrix gelatinosa. 

1. Toxothrix trichogenes (Cholodny, the sheaths. The number and diameters of 

1924) Beger, 1953. (Leptothrix trichogenes the longitudinally placed trichomes are 

Cholodny, Cent. f. Bakt., II Abt., 61, 1924, variable. Giant cells are frequently present. 

296; T'oxo^Arz.T/e/TMgrmea Molisch, Sci. Rept. The sheaths, when empty, decay rapidly. 

Tahoku Imp. Univ., 4 Ser., Biol., 1925, 13; The trichomes may slip out of their sheaths. 

Chlamydothrix trichogenes Naumann, Zent. This species has been cultivated by Teich- 

f. Bakt., II Abt., 78, 1929, 513; Sphaerotilus mann (Vergleichende Untersuchungen iiber 

trichogenes Pringsheim, Biol. Reviews, die Kultur und Morphologie einiger Eisen- 

Cambridge, 24, 1949, 234; Beger, in Beger organismen, Inaug. Diss., Prague, 1935). 

and Bringmann, Zent. f. Bakt., II Abt., Beger and Bringmann (op. cit., 1953, 332) 

107, 1953, 332.) report a form of this species in which the 

tri.cho'ge.nes. Gr. noun thrix, trichis sheaths do not split; the cells are 0.5 by 2.0 

hair; Gr. v. gennao to bear; M.L. adj. tri- to 4.0 microns. 

chogenes hair-producing. Source: This species has been described 

Found in trichomes up to 400 microns in from springs, wells, small rivers, water 

length; composed of rod-shaped cells works and rice fields. 

which are 0.5 by 1.0 to 2.0 microns. Sur- Habitat: Found in cool, fresh, iron-bear- 
rounded by a tubular sheath which splits ing waters, 
later so that arched, fan-shaped groups of 

threads or irregular groups are formed as 2. Toxothrix gelatinosa Beger, 1953. 

the trichomes grow in length. Do not lie in (Beger, in Beger and Bringmann, Zent. f. 

a gelatinous layer. The tubular sheath is Bakt., II Abt., 107, 1953, 333.) 

longitudinally and somewhat spirally stri- ge.la.ti.no'sa. L. part. adj. gelatus con- 

ated with lines about 0.2 micron apart. No gealed; M.L. adj. gelatinosus gelatinous, 

false branching. Iron oxide is deposited in The trichomes are up to 22 microns in 



270 



OEDER 11. CHLAMYDOBACTERIALES 



length; including the sheath, they measure 
1.5 to 1.7 microns in diameter. Several tri- 
chomes arising from the same point and 
each trichome developing a few false 
branches produces a fan-shaped appearance. 
All trichomes end at approximately the 
same distance from the starting point. The 
trichomes are bent so that the entire fan- 
shaped group arches somewhat. The indi- 
vidual cells are rod-shaped, 0.5 by 3.0 mi- 



crons. Iron oxide is deposited in the sheath. 
Around this, a gelatinous mass is formed, 
as much as 22 microns in length and ovoid in 
form. Iron is not deposited in this gelatinous 
mass. 

Source: Found on slides submerged in an 
aquarium in Berlin in which Cahomba was 
growing. 

Habitat : Found in fresh water. 



F.\]VIILY II. PELOPLOCACEAE BEGER, Fam. Nov. 

Pe.lo.plo.ca'ce.ae. M.L. fem.n. Peloploca tj-pe genus of the family; -aceae ending to de- 
note a family; M.L. fem.pl.n. Peloplocaceae the Peloploca family. 

Long, unbranched trichomes usually enclosed in a thin, delicate sheath. Cells within the 
trichomes, when in the living state, contain false vacuoles which are easily discerned by a 
reddish gleam of light which they emit; the cytoplasm of the cell appears bluish white. Gen- 
erally non-motile, but motile species may occur. Reproduction is by transverse fission of the 
cells. Unattached forms found in fresh-water ponds with decomposing algae. 

Key to the genera of family Peloplocaceae, 

I. Trichomes lie parallel to each other in bundles or bands. 

Genus I. Peloploca, p. 270. 

II. Trichomes occur singh\ 

Genus II. Pelonema, p. 271. 

Genus I. Peloploca Lauterborn, 1913. 
(Allgem. bot. Ztschr., 19, 1913, 99.) 

Pe.lo'plo.ca. Gr. adj. pellos or pelos dark-colored; Gr. noun place a twining, a braid or a 
twist; M.L. fem.n. Peloploca dark-colored braid or twist. 

Trichomes of cylindrical, colorless cells with no evident sheath. Occur as motionless 
bundles or bands. Cells contain false vacuoles which emit a reddish gleam of light. Non- 
motile. Occur in fresh-water ponds where Char a sp. is undergoing decomposition. Frequently 
overlooked because the trichomes resemble plant fibers. 

The type species is Peloploca undiilata Lauterborn. 



1. Peloploca undulata Lauterborn, 
1913. (Allgem. bot. Ztschr., 19, 1913, 99.) 

un.du.la'ta. L. adj. undulatus undulated, 
with waves. 

Cells 6 to 10 microns long. The trichomes 
are spirally twisted into wavy bundles that 
are tightly wound together. The bundles 
reach a length of 60 to 150 microns. Non- 
motile. 

Source : Found in Germany in ponds wliere 
Chara sp. was growing. 



Habitat: Presumably widelj' distributed 
in fresh-water ponds. 

2. Peloploca taeniata Lauterborn, 1913. 
(Allgem. bot. Ztschr., 19, 1913, 99.) 

tae.ni.a'ta. L. adj. taeniatus band-like. 

Cells 3.0 to 4.0 microns long. Trichomes 
united into rather broad, frequently twisted 
bands. These may have the appearance of a 
grating or lattice because of the presence 
of pseudo vacuoles in the individual cells. 



FAMILY II. PELOPLOCACEAE 271 

The bands may reach a length of 700 mi- the surface of bottom mud along with 

crons. Beggiatoa, Thiospira, Zoogloea and similar 

Source : Found in Germany in ponds where types of bacteria. 

C/tara sp. was growing; also found by Beger Habitat: Presumably widelj' distributed 

(1954) in decomposing plant materials on in fresh-water ponds. 

Genus II. Pelonema Lauterhorn, 1915. 
(Verhandl. Naturhist.-med. Verein z. Heidelberg, N.F. 13, 1915, 408.) 

Pe.lo.ne'ma. Gr. adj. pellos or pelos dark-colored; Gr. noun neina filament; M.L. neut.n. 
Pelonema dark-colored filament. 

Long, unbranching trichomes, occurring singly, which are either straight or spirally 
twisted. The trichomes are enclosed in a very thin, delicate sheath. Non-motile, but may be- 
come motile. Within the trichomes are C3'lindrical, colorless cells which contain one or 
several to many false vacuoles which emit a reddish gleam of light. Found on the surfaces 
of ponds and lakes w^hich contain decomposing algae and which are poorly aerated. 

The type species is Pelonema temie Lauterborn. 

Key to the species of genus Pelonema. 

I. Cells contain a single false vacuole. 

A. Cells 8 to 12 microns long; trichomes are straight and attain a length of up to 300 
microns. 

1. Pelonema tenue. 

B. Cells 4 to 6 microns long; trichomes are straight and are 200 or more microns long. 

2. Pelonema hyalinum. 
II. Cells contain several to many false vacuoles. 

A. Trichomes are straight, measuring up to 500 microns in length. 

3. Pelonema pseudovacuolatum. 

B. Trichomes are spirally twisted, reaching a length of 40 to 160 microns. 

4. Pelonema spirale. 

1. Pelonema tenue Lauterborn, 1915. hy. a. li'num. Gr. adj. ^T/ahwi/s of crystal, 
(Verhandl. Naturhist.- med. Verein z. glass; M.L. adj. hyalinus hyaline. 
Heidelberg, N.F. 13, 1915, 408.) Straight trichomes which measure 200 or 

te'nu.e. L. adj. tenuis slender. more microns in length. The cells, 2 by 4 to 

Straight trichomes, up to 300 microns 6 microns, contain a single false vacuole 

long, which may become motile when the which is quite large and slightly refractive; 

water in which they are growing is low in the vacuole is rectangular in shape and has 

oxygen content. Cells are 2 by 8 to 12 mi- rounded edges. 

crons. Each cell contains a single false Source: From water from Little Ploner 

vacuole which nearly fills the cell; the Lake, Schleswig-Holstein, Germany, 
vacuole is irregular in shape and emits but Habitat: Found in the upper algae-con- 

a small reddish gleam of light. taining layers of deep fresh-water lakes. 

Source: From pools in the Rheinebene, 
Germany, where Chara was growing. 3. Pelonema pseudovacuolatum Lau- 

Habitat: Presumably widely distributed terborn, 1915. (Verhandl. Naturhist.- med. 

in fresh-water ponds and lakes which con- Verein z. Heidelberg, N.F. 13, 1915, 408.) 
tain decomposing algae. pseu.do. va.cu.o.Ia'tum. Gr. adj. pseudes 

false; L. adj. vacuus empty; M. L. noun 

2. Pelonema hyalinum Koppe, 1923. vacuola a vacuole; M.L. adj. pseudovacuola- 
(Pelonema hyalina (sic) Koppe, Archiv. f. tns having false vacuoles. 
Hydrobiologie, H, 1923, 625.) Straight trichomes measuring up to 500 



272 ORDER II. CHLAMYDOBACTERIALES 

microns in length. The cells are 2 by 4 mi- 1915. (Verhandl. Naturhist.-med. Verein z. 

crons and possess several small false vacu- Heidelberg, N.F. 13, 1915, 408.) 

oles which are sharply but irregularly out- spi.ra'le. Gr. noun spira a spiral; M.L. 

lined. The cytoplasm of the cells emits a adj. spiralis spiral. 

marked bluish gleam of light. Spirally twisted trichomes, 1.0 to 1.5 by 

Source: From pools and shallow lakes 40 to 160 microns, with a wave length of 8 

which contained an abundance of decom- to 14 microns. The cells contain numerous, 

posing algae. small but long false vacuoles. 

Habitat: Found in fresh water. Source: From a pool in Germany rich in 

Chara. 

4. Peloneina (?) spirale Lauterborn, Habitat: Found in fresh water. 



FAMILY III. CRENOTRICHACEAE HANSGIRG, 1888. 

(Oesterr. bot. Ztschr., 36, 1888, 228.) 

Cre.no.tri.cha'ce.ae. M.L. fem.n. Crenothrix type genus of the family; -aceae ending to 
denote a family; M.L. fem.pl.n. Crenotrichaceae the Crenothrix familJ^ 

Trichomes attached to a firm substrate and show differentiation of base and tip. Un- 
branched or show false branching. Sheaths may be thin, delicate and not encrusted with 
oxides of iron or manganese, or they may be plainlj^ visible, thin and colorless at the tip and 
thick and encrusted with iron or manganese oxides at the base. Cells disc-shaped to cylindri- 
cal, dividing to produce spherical, non-motile conidia. Individual cells may also slip out of 
the sheath to grow into new trichomes. Found in fresh and salt waters. 

Key to the genera of family Crenotrichaceae. 

I. Attached trichomes which are swollen at the free end. 

A. Sheath thick, storing iron or manganese o.xides. 

Genus I. Crenothrix, p. 272. 

B. Sheath very delicate, always colorless. 

Genus II. Phragmidiothrix, p. 273. 
II. Attached trichomes which are tapered at the free end. 

Genus III. Clonothrix, p. 274. 

Genus I. Crenothrix Cohn, 1870. 
(Beitr. z. Biol. d. Pflanz., 1, Heft 1, 1870, 108.) 

Cre'no.thrix. Gr. noun crenus a fountain, spring; Gr. noun thrix, trichis a hair; M.L. 
fem.n. Crenothrix fountain hair. 

Trichomes attached to a firm substrate and swollen at the free end. Unbranched or show 
false branching. The sheaths surrounding the trichomes are plainly visible, thin and color- 
less at the tip and encrusted with iron or manganese o.xides at the base. Cells disc-shaped 
to cylindrical, dividing to produce spherical, non-motile conidia of two types: micro- and 
macroconidia. Individual cells may also slip out of the sheath and form new trichomes. 
Found in stagnant and running waters which contain organic matter and iron salts. 

The type species is Crenothrix polyspora Cohn. 

1. Crenothrix polyspora Cohn, 1870. noun spon/s a seed; M.L. noun spora a spore; 

(Beitr. z. Biol. d. Pflanz., 1, Heft 1, 1870, M.L. adj. polysporus many-spored. 

108.) Trichomes long (up to 1 cm), articulated, 

po.ly'spo.ra. Gr. adj. poly many; Gr. unbranched and sessile. There is consider- 



FAMILY III. CRENOTRICHACEAE 



273 



able variation in the diameter of the indi- 
vidual trichomes, the base measuring 1.5 
to 5.0 microns and the swollen tip measur- 
ing 6.0 to 9.0 microns. Each trichome is sur- 
rounded b}' a colorless sheath which later 
may become rust-colored and heavily en- 
crusted, especially at the base, with deposi- 
tions of ferric hydroxide and, to a lesser 
e.xtent, manganese oxides. The ensheathed 
trichomes may reach a diameter of 12 mi- 
srons or more. Cells within the trichomes 
are usually about 1.5 times as long as they 
are wide and are more or less rectangular in 
shape. 

During reproduction the cells divide by 
longitudinal and transverse fission into non- 
motile conidia of two types: microconidia, 
which are 1 to 2 microns in diameter, and 
macroconidia, which measure about 5 
microns in diameter; intermediate forms 
may also occur. When the tip of the sheath 
ruptures, the conidia are extruded; these 
may attach themselves to some object and 
grow into trichomes, or they may germinate 
upon the exterior of the sheath from which 
they were liberated, giving rise to new tri- 
chomes attached to the surface of the older 
one, thus simulating false branching. The 
conidia often form a zoogloeal mass, but 
only in the presence of dissolved iron. 

In addition to the above-mentioned types 
of reproductive cells, Cohn (ibid., 120) ob- 
served a third structure which he condi- 
tionall}'^ alluded to as a spore. These cells 
originate from the swollen terminal cell 
which is usually ellipsoidal in shape and 
sometimes as much as seven times as long 
as it is wide (3.67 by 26.25 microns). The 
protoplasm of this terminal cell becomes 
finely granular and eventually emerges from 
the sheath. From these cells, short, color- 
less Oscillaria-like trichomes are produced 
which contain no more than eight cylindri- 
cal cells measuring 5 to 6 by 10 to 12 microns. 
The trichomes have a characteristic, slow, 



gliding motion and are surrounded by a fine, 
transparent membrane, but no sheath. 
Subsequent authors, when describing this 
species, have usually failed to mention this 
third type of reproductive cell observed by 
Cohn. 

Cultivation: Has not been grown on 
artificial media in pure culture. Grows 
readily in water containing organic matter 
regardless of the iron content of the water. 

Related species: Cholodny believed 
Clonothrix fusca to be identical with Creno- 
thrix polyspora. However, Clonothrix ftisca 
shows genuine false branching and produces 
conidia by fission in only one plane so that 
the trichomes taper toward the tip instead 
of expanding (see Kolk, Amer. Jour. Bot., 
25, 1938, 11, for a differentiation of these 
two species). 

Comments: Zopf (Entwicklungsgesch. 
Unters. (i. Crenoihrix polyspora, die Ursache 
der Berliner Wasserkalamitat. Berlin, 1879, 
2) regards Leptothrix kuehniana Rabenhorst 
as identical with Crenothrix polyspora Cohn, 
and there seems to be much evidence in 
favor of considering the tw-o species as 
identical. If Cohn's organism proves to be 
identical with Rabenhorst's, then the spe- 
cific epithet kuehniana has priority over 
polyspora; however, until the relationship 
of the two organisms has been clarified, the 
name Crenothrix polyspora is retained here. 

Source: This organism is wide-spread in 
water pipes, drain pipes and springs w^here 
the water contains iron. It frequently fills 
pipes under such circumstances and causes 
a real nuisance. Found by Cohn in samples 
of water from springs in the neighborhood 
of Breslau, Germany. 

Habitat: Found in stagnant or running 
waters containing organic matter and iron 
salts. Harmless, but frequently becomes 
bothersome in w^ater pipes and city water 
supplies; grows as thick, brownish masses. 



Genus II. Phragmidiothrix Engler, 1883. 

(Vierter Ber. d. Commission z. wissensch. Unters. d. deutsch. Meere in 
Kiel fiir 1877 bis 1881, I Abt., 1883, 187.) 

Phrag.mi'di.o.thrix. Gr. noun phragma fence; Gr. noun eidus form, shape; Gr. noun 
thrix, trichis hair; M.L. fem.n. Phragmidiothrix fence-like hair. 
Trichomes are articulated, unbranched and attached, the free ends being swollen. Sur- 



274 



ORDER II. CHLAMYDOBACTERIALES 



rounding the trichomes are very thin, delicate, colorless sheaths which do not store iron or 
manganese compounds. The cells are small and disc-shaped and are uniform in size. Conidia 
of the same diameter as the cells are produced. Found in salt water. 

Hansgirg (Bot. Ztg., 49, 1891, 313) concluded that Phragmidiothrix should be included in 
the genus Crenothrix, and that the genus Crenothrix should be divided into two sections, 
Eitcrenothrix and Phragmidiothrix. 

The type species is Phragmidiothrix viuUise'ptata (Engler) Engler. 



1. Phragmidiothrix niultiseptata 

(Engler, 1882) Engler, 1883. (Beggiatoa 
jnultisepiata Engler, Verhandl. bot. Ver. 
Brandenburg, U, 1882, 19; Engler, Vierter 
Ber. d. Commission z. wissensch. Unters. d. 
deutsch. Meere in Kiel fur 1877 bis 1881, I 
Abt., 1883, 187; also see Zopf, Die Spaltpilze, 
1883, 104.) 

mul.ti.sep.ta'ta. L. mas.n. multus much; 
L. adj. septatus fenced; M.L. adj. multisep- 
tatus much-fenced, with many septa. 

Colorless trichomes, several millimeters 
long, which form grayish white tufts. The 
trichomes are sessile; when young they are 
1.5 microns wide, but when older they meas- 
ure 2 to 3 microns at their bases and 5 to 6 
microns at their tips. Very thin, delicate 
sheaths which are not encrusted with iron 
or manganese oxides surround the tri- 



chomes. The cells are disc-shaped, their 
width being 1.5 to 4.0 microns while their 
length is only }4: to l^ this size. Each cell 
has a very thin, colorless membrane and 
some hyaline granules. 

When mature, the cells in the upper por- 
tion of the trichomes divide longitudinally 
and transversely and form uniformly sized 
conidia (1 micron in diameter). These co- 
nidia may be extruded, may become free by 
decomposition of the sheath, or they may 
germinate within the sheath. The extruded 
conidia may produce zoogloeal masses be- 
fore they germinate. 

Source: From the body of a crustacean 
(Gammarus locusta) from sea water; also 
found on seaweeds in polluted water on the 
shores of the northern Adriatic. 

Habitat : Found in polluted salt water. 



Genus III. Clonothrix Roze, 1896. 

(Roze, Jour, de Botanic, 10, 1896, 325; also proposed independently 
by Schorler, Cent. f. Bakt., II Abt., 12, 1904, 689.) 

Clo'no.thrix. Gr. noun clon, clonis twig, slip; Gr. noun thrix, trichis hair; M.L. fem.n. 
Clonothrix twig hair. 

Attached trichomes showing false branching as in Sphaerotihis. Sheaths organic, encrusted 
with iron or manganese, broader at the base and tapering toward the tip. Cells colorless, 
cylindrical. Reproduction by spherical conidia formed in chains by transverse fission of 
cells; conidia formation acropetal, limited to short branches of the younger portions of the 
trichomes. 

The type species is Clonothrix putealis (Kirchner) Beger. 



1. Clonothrix putealis (Kirchner, 1878) 
Beger, 1953. {Glaucothrix putealis Kirchner, 
Kryptogamen-Flora von Schlesien, 2, 1, 
1878, 229; Clonothrix fusca Roze, Jour, de 
Botanic, 10, 1896, 325; Beger, in Beger and 
Bringmann, Zent. f. Bakt., II Abt., 107, 
1953, 327.) 

pu.te.a'lis. L. adj. putealis belonging to a 
well. 

Ensheathed trichomes, up to 0.6 mm long, 
which show false branching and which taper 
towards the tip; the bases of the trichomes 



measure 7 microns and the tips measure 2 
microns in diameter. The sheaths may be- 
come encrusted with oxides of manganese 
and/or iron, particularly those of manga- 
nese. Sheath encrustations may reach a 
thickness of 24 microns when manganese 
oxides are prevalent and 10 microns when 
iron oxides are abundant. Cells cj'lindrical 
with rounded ends, 2 by 10 microns, be- 
coming larger toward the base and smaller 
toward the tips of the trichomes. 
Multiplication by extrusion of single cells 



FAMILY III. CRENOTRICHACEAE 



275 



or by rather uniform, spherical, non-motile 
conidia formed into short trichomes in 
chains of 2 to 6 or more, their diameters 
being about 2 microns. 

Historical: This organism was described 
by Roze as a blue-green alga, but subse- 
quent observers have failed to find pigment. 
It was described independently by Schorler 
(Cent. f. Bakt., II Abt., 12, 1904, 689) who 
also gave it the name Clonothrix fusca. 
Cholodny considered it identical with 



Crenolhrix polyspora, but Kolk (Amer. 
Jour. Bot., 25, 1938, 11) has clearly differ- 
entiated these species. 

Source : From a well in Proskau, Schlesien. 

Habitat: Widely distributed in rivers 
and streams with gravelly, manganese- 
bearing bottoms; also found in water works 
and pipe lines, where it may cause technical 
difficulties. May occur in dark brown masses 
that are large enough to be seen readily in 
tap water. 



ORDER III. HYPHOMICROBIALES DOUGLAS, Ordo Nov, 



Hy.pho.mi.cro.bi.a'les. M.L. fem.pl. n. Hyphomicrobiaceae type family of the order; 
-ales ending to denote an order; M.L. fem.pl.n. Hyphomicrohiales the Hyphomicrobiaceae 
order. 

Multiplication is by budding or by budding and longitudinal fission. Buds may be sessile 
or may be borne at the tip of a slender filament which arises from the pole of a mature cell 
or from a filament connecting two cells. Cells may occur singly or in pairs but are found more 
commonly in aggregates. In some types the aggregates consist of groups of cells attached 
to a surface by stalks which appear to radiate from a common holdfast; in others the ag- 
gregates consist of free-floating cell groups in which the cells are attached to one another 
by the filament engendered in the budding process. Branching of the filament may result 
in groups which contain several hundred cells. Cells are ovoid, ellipsoidal, spherical or 
pyriform. If motile, the cells possess a single polar flagellum. Specialized resting stages have 
not been found. Gram-negative so far as known. Metabolism may be heterotrophic or 
photosynthetic. Found in the mud and water of fresh-water ponds and streams; also para- 
sitic on fresh-water Crustacea. 

Key to the Families of Order Hyphomicrobiales. 

I. Buds borne upon filaments. 

Family I. Hyphomicrobiaceae, p. 276. 
II. Buds sessile. 

Family II. Pasteuriaceae, p. 278. 



FAMILY I. HYPHOMICROBIACEAE BABUDIERI, 1950. 
(Rendiconti dell'Istituto Superiore di Sanita, 13, 1950, 589.) 

Hy.pho.mi.cro.bi.a'ce.ae. M.L. neut.n. Hyphomicrobium type genus of the family; 
-aceae ending to denote a family; M.L. fem.pl.n. Hxjphomicrobiaceae the Hyphomicrobium 
family. 

These organisms occur mainly as free-floating groups in which the cells are attached to 
one another by a slender, sometimes branched, filament. Daughter-cell formation is initi- 
ated by the outgrowth of a filament from the pole of a mature cell or from some point on a 
filament connecting two mature cells. The daughter cell is formed by enlargement of the tip 
of the filament. Gram-negative. 

Key to the genera of family Hyphomicrobiaceae. 

I. Chemoheterotrophic. Motile. 

Genus I. Hyphomicrobium, p. 277. 

* New material prepared by and old material rearranged by Prof. H. C. Douglas, Depart- 
ment of Microbiology, School of Medicine, University of Washington, Seattle, Washington, 
December, 1953. 

276 



FAMILY I. HYPHOMICROBIACEAE 



277 



II. Photoheterotrophic. Non-motile. 



Genus II. Rhodomicrohium, p. 277. 



Genus I. Hyphomicrobium Stutzer and Hartleb, 1898. 

(Mitteil. d. landwirtsch. Inst. d. k. Univ. Breslau, 1898; abst. in Cent. f. Bakt., II Abt., 

6, 1899, 678.) 

Hy.pho.mi.cro'bi.um. Gr. noun hyphe thread; Gr. adj. micrus small; Gr. noun hius life; 
M.L. neut.n. Hyphomicrobium thread (-producing) microbe. 

Daughter cells may remain attached to the filaments which connect them to the mother 
cells or may tear free of the filament as the result of active movement by means of a single, 
polar flagellum. Gram-negative. Non-pigmented. Metabolism is chemoheterotrophic and 
oxidative. Aerobic. Found in soil and in fresh water. 

The type species is Hyphomicrobium vulgare Stutzer and Hartleb. 



1. Hyphomicrobium vulgare Stutzer 
and Hartleb, 1898. (Saltpeterpilz, Stutzer 
and Hartleb, Cent. f. Bakt., II Abt., 3, 
1897, 621; Stutzer and Hartleb, Mitteil. d. 
landwirtsch. Inst. d. k. Univ. Breslau, 1898; 
abst. in Cent. f. Bakt., II Abt., 5, 1899, 
678.) 

vul.ga're. L. adj. vxdgaris common. 

Description taken from Stutzer and 
Hartleb {loc. cit.), Kingma-Boltjes (Arch, 
f. Mikrobiol., 7, 1936, 188) and Mevius 
(Arch. f. Mikrobiol., 19, 1953, 1). 

Mature cells are ovoid, measuring 0.5 
by 1.0 nucron; immature cells are spherical. 
Motile bj- means of a single, polar flagel- 
lum. Daughter cells are borne on filaments 
measuring approximately 0.2 micron or 
less in diameter and varying in length from 
one to several times the length of mature 
cells. The predominant growth habit is that 
of a dense clump of cells from which fila- 
ments radiate outward. Branching of the 
filament occurs but is not common. 
Daughter cells may tear free of the fila- 
ments and e.xist as single, motile cells with 
motility sometimes persisting even after 
the cell has produced a filament of consid- 
erable length. Cells in pairs, connected 
by a filament, are common. Gram-nega- 
tive. 

Gelatin: No growth. 



Formate-nitrate agar or silica gel plates: 
Colonies are colorless, 0.5 to 1.0 mm in di- 
ameter, slightly elevated, entire. 

Peptone agar colonies: Much smaller 
than those above. 

Peptone broth: Poor growth. 

Formate-nitrate broth: Growth occurs 
as a light, cream-colored, granular sedi- 
ment. 

Chemoheterotrophic, oxidative. Growth 
occurs in mineral media at pH 7.0 to 7.5 
with ammonium or nitrate as a nitrogen 
source and formate, formaldehyde, meth- 
anol, acetate or lactate as a carbon source. 
Some growth occurs in mineral media with- 
out an added carbon source at the expense 
of organic compounds in the air. 

Sucrose not attacked. 

Asparagine not utilized. 

Aerobic. 

Temperature range for growth, 20° to 
37° C. 

Source: Isolated from soil and water. 
Commonly found in enrichment cultures 
for nitrifying bacteria and in activated 
sludge. Babudieri (Rendiconti Istit. Super, 
di Sanita, Roma, 13, 1950, 589) has found 
this species as a contaminant in Leptospira 
canicola cultures. 

Habitat: Widely distributed in soil and 
in fresh water. 



Genus II. Rhodomicrobium Duchow and Douglas, 1949. 

(Jour. Bact., 58, 1949, 409.) 

Rho.do.mi.cro'bi.um. Gr. noun rhodum the rose; Gr. adj. micrus small; Gr. noun bius 
life; M.L. neut.n. Rhodomicrobium red (-producing) microbe. 
The daughter cells remain attached to the filaments connecting them to the mother cells. 



278 



ORDER III. HYPHOMICROBIALES 



Non-motile. Gram-negative. Colonies are salmon-pink to orange-red in color. Photohetero- 
trophic. Anaerobic. Found in mud and in fresh water. 
The type species is Rhodomicrobium vnnnielii Duchow and Douglas. 



1. Rhodomicrobium vannielii Duchow 
and Douglas, 1949. (Duchow and Douglas, 
Jour. Bact., 58, 1949, 409; also see Murray 
and Douglas, Jour. Bact., 59, 1950, 157; 
and Volk and Pennington, Jour. Bact., 
59, 1950, 169.) 

van.niel'i.i. M.L. gen. noun vannielii of 
van Niel; named for C. B. van Niel, an 
American bacteriologist. 

Mature cells are ovoid, measuring 1.2 by 
2.8 microns; immature cells are spherical. 
Non-motile. The cells are connected by 
filaments which are approximately 0.3 mi- 
cron in diameter and from one to several 
times the length of a mature cell. A mature 
cell may produce as many as three daughter 
cells: one by formation of a primary fila- 
ment from the pole of the cell, and one or 
two more by lateral outgrowths of new fila- 
ments from the primary filament upon 
which the first daughter cell is borne. Be- 
cause of the tendency of the cells to remain 
attached to the filament, the predominant 
growth habit is that of an aggregate con- 
taining many cells. Gram-negative. 

Agar: In shake tubes, colonies are dark 



orange-red, irregular, 2 to 3 mm in diameter 
and have a rough, convoluted surface. 

Broth: Turbid in young cultures, becom- 
ing granular and flocculent; salmon -pink 
to deep orange-red, depending on the den- 
sity of growth. 

Photoheterotrophic. Cells contain bac- 
teriochlorophyll and carotenoid pigments. 
Growth occurs in the presence of light in a 
mineral medium containing an organic hy- 
drogen donor and bicarbonate; organic 
growth factors are not required. Suitable 
hydrogen donors are ethanol, propanol, 
butanol, acetate, propionate, butyrate, 
valerate, caproate, lactate and malate. 

Glucose, mannose, fructose, mannitol, 
citrate, tartrate, formate, thiosulfate and 
sulfide are not utilized. 

Anaerobic. 

Optimum temperature, between 25° and 
30° C. 

Source: Isolated from mud and water 
from Washington State. 

Habitat: Commonly found in mud, pond, 
lake and stream waters. 



FAMILY II. PASTEURIACEAE LAURENT, 1890, EMEND. 
HENRICI AND JOHNSON, 1935. 

(Laurent, Compt. rend. Acad. Sci., Paris, 3, 1890, 754; Henrici and Johnson, 
Jour. Bact., 30, 1935, 84.) 

Pas.teu.ri.a'ce.ae. M.L. fem.n. Pasteuria type genus of the family; -aceae ending to 
denote a family; M.L. fem.pl.n. Pasteuriaceae the Pasteuria family. 

Stalked bacteria with spherical or pear-shaped cells; if cells are elongated, the long axis 
of the cell coincides with the axis of the stalk. Stalks may be very short or absent, but 
when present they are usually very fine and at times arranged in whorls attached to a 
common holdfast. Cells multiply by longitudinal fission and/or by budding. Mostly peri- 
phytic; one species is parasitic. 

The descriptions of the members of this family are largely based upon microscopic exam- 
inations of collected materials such as parasitized daphnias (fresh-water Crustacea) or 
glass slides submerged at various depths for about two weeks in Lake Alexander, Minne- 
sota (Henrici, Jour. Bact., 25, 1932, 277). A few crude cultures were obtained in two liquid 
media: one containing a mineral solution with precipitated cellulose and ammonium salts 
as a source of nitrogen, the other being a solution of MgS04 and K2HPO4 in tap water to 



FAMILY II. PASTEURIACEAE 



279 



which bits of the exoskeleton of marine crabs were added. No growth took phice on agar 
media so that no pure cultures were obtained. Cultures were incubated at room temperature 
in the dark. Further information regarding the organisms belonging to the genera of this 
family is greatly needed. 

Key to the genera of family Pasteuriaceae. 

I. Stalks lacking; cells sessile. 

Genus I. Pasteuria, p. 279. 
II. Stalks long and slender, often in whorls. 

Genus II. BlastocauUs, p. 279. 

Genus I. Pasteuria Metchnikoff, 1888. 
(Ann. Inst. Past., 2, 1888, 166.) 

Pas.teu'ri.a. M.L. gen.n. Pasteuria of Pasteur; named for Louis Pasteur, the French 
scientist. 

Pear-shaped cells attached to each other or to a firm substrate by holdfasts secreted at 
the narrow end. Multiplication is by longitudinal fission and by budding of spherical or 
ovoid cells at the free end. Non-motile. Non -pigmented. Parasitic on fresh-water Crustacea. 

The type species is Pasteuria ramosa Metchnikoff. 

1. Pasteuria ramosa Metchnikoff, 1888. found by Henrici and Johnson {ibid., 71 

(Ann. Inst. Past., 2, 1888, 166.) and 77) in Lake Alexander, Minnesota; 

ra.mo'sa. L. adj. ramosMS much-branched, these appeared frequently on glass slides 

Cells 1 to 2 by 4 to 5 microns. Non-motile, submerged in the lake water; they produced 
Non-pigmented. Cells grow attached to reproductive bodies apparently by budding 
each other in cauliflower-like masses, multi- rather than by an endogenous formation, 
plying by longitudinal fission or by intra- Photomicrographs are shown in Henrici 
cellular bodies which are extruded as buds, and Johnson {ibid., 93, plate 3, fig. 4) . ZoBell 
apparentlj^ reproductive in nature; at times and Allen (Proc. Soc. Exp. Biol, and Med., 
these colonies break up into smaller ones 30, 1933, 1409) and ZoBell and Upham (Bull, 
and continue to separate until all of the Scripps Inst. Oceanography, LaJolla, Cal- 
individual cells are liberated. Cells and ifornia, 5, 1944, 243) used a submerged- 
methods of reproduction resemble those slide technique in sea water and found simi- 
of Chamaesiphon, a genus of blue-green lar bacteria. 

algae (Henrici and Johnson, Jour. Bact., Source: From the body cavities of Daph- 

30, 1935, 71). Gram stain not recorded. nia pulex and D. magna. 

Related species: Free-living organisms Habitat: Parasitic on fresh-water crus- 

which resembled Pasteuria ramosa were tacea so far as known. 

Genus II. Blastocaulis Henrici and Johnson, 1935. 
(Jour. Bact., 30, 1935, 84.) 

Blas.to.cau'lis. Gr. noun blastus a sprout, shoot, bud; Gr. noun caulis a stalk; M.L. 
fem.n. Blastocaulis a bud stalk. 

Pear-shaped or globular cells attached to a firm substrate by long, slender stalks with a 
holdfast at the base; stalks may occur singly or may arise in clusters from a common hold- 
fast. Not cultivable on artificial media. Found on firm substrates in fresh water. 

The type species is Blastocaulis sphaerica Henrici and Johnson. 

1. Blastocaulis sphaerica Henrici and sphae'ri.ca. Gr. adj. sphaericus spherical. 

Johnson, 1935. (Jour. Bact., 30, 1935, 84.) Cells spherical, 1 to 2 microns in diameter. 



280 



ORDER III. HYPHOMICROBIALES 



The cells are attached to long, slender stalks 
which radiate from a common center; as 
many as 8 stalks may be attached to a com- 
mon holdfast; usually thej' are attached 
directly to a glass slide, occasionally to 
algae or other organisms or to some amor- 
phous debris. Multiplication is by budding, 
the buds being globular in shape. The 
smaller cells stain solidly, but the larger 
cells that are budding show a differentiation 
of the protoplasm: the free end stains deeply 
while that part of the cell which is attached 
to the stalk stains more faintly. Young cells 
are Gram-positive, but budding individuals 
are Gram-negative. 

Temperature relations: Found only in 
lake water where temperatures do not ex- 
ceed 23° C. 

Comments: It is believed that the char- 
acteristic growth of this organism in whorls 



may be best explained by assuming that 
when the buds germinate they first undergo 
a simple fission, perhaps producing clusters 
of cells, and that then, from these clusters, 
the individual cells secrete stalks which 
thus radiate from a common holdfast. 

Related species: Similar stalked bacteria 
which reproduce by budding are illustrated 
by Henrici and Johnson (ibid., 77 and 91) 
but are not named or described in detail. 

Source: From glass slides submerged in 
Lake Alexander, Minnesota. 

Habitat: Presumably widely distributed 
in fresh-water ponds. Does not occur closer 
to the shore than the 2-meter contour. 
Found constantly in the open lake at all 
depths up to 13 meters. Occurs more abun- 
dantly in the fall months than in the sum- 



ORDER IV. EUBACTERIALES BUCHANAN, 1917. 



(Jour. Bact., 2, 1917, 102.) 

Eu.bac.te.ri.a'les. Gr. pref. eu- well, true; Gr. neut.n. hacterium a small rod; -ales end- 
ing to denote an order; M.L. fem.pl.n. Euhacteriales the order of the true bacteria. 

Simple, undifferentiated, rigid cells which are either spherical or straight rods. In some 
families, for e.xample Corynehacteriaceae, a certain amount of pleomorphism occurs. Only 
the simplest forms of branching occur, and these only rarely. There are many non-motile 
as well as motile species. The flagella are usually arranged peritrichously, but monotrichous 
species do occur in groups where the flagellation is normally peritrichous; such conditions 
appear to have been developed from ancestral peritrichous species. Tj'pical endospores 
occur in one family (Bacillaceae) . All of the species in certain families are definitely Gram- 
negative; in other families and groups, where the majority of species are Gram-positive, 
at least in certain stages of growth, species occur which lose their Gram stain so readily 
that they are generally classed as Gram-negative. Reproduction is by transverse fission; 
occasionally the cells divide in two or three planes perpendicular to each other, thereby 
forming tetrads or packets of eight cells. The pigments of chromogenic species are com- 
monly non-water-soluble and of a carotenoid nature; other pigments do occur however, 
some of which show slight powers of diffusion into agar media. None of these pigments have 
the ability to carry out photosynthesis. The order includes saprophytes, parasites and 
many pathogenic species; the latter cause diseases of both animals and plants. Found in 
salt and fxesh waters, air, soil and in the bodies of animals and plants. 

Key to the families of order Euhacteriales. 

I. Cells rod-shaped (rarely large, yeast-like cells). Gram-negative. 
A. Aerobic or facultatively anaerobic. 

1. Large ovoid to rod-shaped cells which may be yeast-like in appearance. Free- 
living in soil. Fix free nitrogen. 

Family I. Azofobacteraceae, p. 283. 

2. Not as above. 

a. Heterotrophic rods which may not require organic nitrogen for growth. 
Usually motile by means of one to six flagella. Frequently form nodules or 
tubercles on roots of plants or show violet chromogenesis. Colonies usually 
large and slimy, especially on mannitol agar. 

Family II. RMzobiaceae, p. 285. 
aa. Not as above. 

b. Straight rods which grow readily on ordinary peptone media. May or 
may not ferment sugars anaerobically with the production of organic 
acids. 
c. Glucose usually attacked oxidatively or not at all. Only rarely are 
species able to ferment glucose anaerobically. Produce little or no 
acid in litmus milk. May or may not reduce nitrates. Many yellow 
chromogens. Some species digest agar, others chitin. Primarily 
found as saprophytes in foods, in soil and in fresh and salt water. 
Family III. Achromobacteraceae, p. 296. 

281 



282 ORDER IV. EUBACTERIALES 

cc. Ferment glucose anaerobically, frequently producing visible gas 
(CO2 + H2) from glucose and sometimes lactose. Reduce nitrates 
(rare exceptions). Frequently found in the alimentary, respiratory 
and urinary tracts of vertebrates, others are free-living, while still 
others are plant pathogens. 

Famil}^ IV. Enterobacteriaceae, p. 332. 
bb. Usuallj^ small, motile or non-motile rods. Obligate animal parasites 
which usually require body fluids for growth. Man}' fail to grow on 
ordinar}^ media. The majority do not ferment glucose anaerobically. 
Family V. Brucellaceae , p. 394. 
B. Anaerobic to microaerophilic, rod-shaped organisms which sometimes show branch- 
ing. 

Family VI. Bacteroidaceae, p. 423. 
II. Cells spherical to rod-shaped. Usually Gram-positive, though some cocci and anaerobic 
spore-forming rods lose the Gram stain readil3^ 

A. Cells do not form endospores. 

1. Cells spherical, occurring in masses, tetrads or packets of eight cells. 

a. Spherical cells. Gram-positive. Aerobic or anaerobic. 

Family VII. Micrococcaceae, p. 454. 
aa. Cells spherical. Gram-negative. Aerobic or anaerobic. Frequently occur 
in pairs. 

Family VIII. Neisseriaceae, p. 480. 

2. Cells either spherical, occurring in chains, or rod-shaped. Gram-positive, but 
cells may lose the Gram stain readily in old cultures. 

a. Cells rod-shaped, no pleomorphism or branching of cells. Rarely or never 
ferment glucose anaerobically. 

Family IX. Brevibacteriaceae, p. 490. 
aa. Not as above. 

b. Gram-positive cocci and rods which frequentl}' form chains of cells. 
Cells ferment sugars anaerobically with the production of lactic, acetic, 
propionic, butyric, etc. acids. Microaerophilic to anaerobic, 
c. Homo- and hetero-fermentative cocci and rods whose chief product 
in fermentation is lactic acid. Do not reduce nitrates. 
Family X. LactobaciUaceae, p. 505. 
cc. Rod-shaped bacteria whose distinctive product in fermentation is 
propionic acid, butyric acid or ethanol. All produce CO2 . 

Family XI. Propionibacteriaceae, p. 569. 
bb. Cells generally rod-shaped but wedge and club forms are common. The 
cells are usually found in angular or picket formations due to snapping 
division. Old cells are frequently Gram-negative. Not active in the an- 
aerobic fermentation of sugars. May or may not reduce nitrates. 
Family XII. Corynebacieriaceae, p. 578. 

B. Rod-shaped cells that produce endospores. Aerobic and anaerobic. Some anaerobic 
species lose the Gram stain readily. 

Family XIII. Bacillaceae, p. 613. 



FAMILY I. AZOTOBACTERACEAE 



283 



FAMILY I. AZOTOBACTERACEAE BERGEY, BREED AND MURRAY, 1938.* 

(Azotobacleriaceae (sic) Bergey, Breed and Murray, Preprint, Manual, 5th ed., 
October, 1938, v and 71.) 

A.zo.to.bac.te.ra'ce.ae. M.L. mas.n. Azotobacter tj-pe genus of the familj^; -aceae end- 
ing to denote a family; M.L. fem.pl.n. Azotobacteraceae the Azotobacter family. 

Relatively large rods or even cocci, sometimes almost yeast-like in appearance. Cells 
without endospores. The type of flagellation in this genus has been definitely established 
as peritrichous. Gram-negative. Obligate aerobes, usually growing in a film on the surface 
of the culture medium. Capable of fixing atmospheric nitrogen when provided with carbo- 
hydrate or other energy source. Grow best on media deficient in nitrogen. Soil and water 
bacteria. 

There is a single genus. 

Genus I. Azotobacter Beijerinck, 1901. 
(Cent. f. Bakt., II Abt., 7, 1901, 567.) 

A.zo.to.bac'ter. Gr. adj. azons without life; Fr. noun azote nitrogen; M.L. mas.n, bacter 
the masculine equivalent of Gr. neut.n. bactrum a rod or staff; M.L. mas.n. Azotobacter 
nitrogen rod. 

Description same as for the family. 

The type species is Azotobacter chroococcum Beijerinck. 



1. Azotobacter chroococcum Beijer- 
inck, 1901. (Cent. f. Bakt., II Abt., 7, 1901, 
567; also see ibid., 9, 1902, 3.) 

chro.o.coc'cum. Gr. noun chroa color, 
complexion; Gr. noun coccus a grain; M.L. 
neut.n. chroococcum colored coccus. 

Rods, 2.0 to 3.0 by 3.0 to 6.0 microns, 
occurring in pairs and packets and occasion- 
allj^ in chains. The cells show three or four 
refractile granules. The organisms are sur- 
rounded by a slimy membrane of variable 
thickness, usually becoming brownish in 
older cultures, due possibly to the con- 
version of tyrosine to melanin. The coloring 
matter is insoluble in water, alcohol, ether 
or chloroform. Motile bj' means of numerous 
peritrichous flagella (Hofer, Jour. Bact., 
47, 1944, 415). Gram-negative. 

Grows in absence of organic nitrogen. 

Gelatin colonies: Very small, circular, 
yellow, granular, later becoming yellowish 
brown. 

Gelatin stab: Onlj' slight growth in the 
stab. No liquefaction. 

Mannitol agar stab: Gray, may become 
brownish. 

Nutrient broth: No growth even in the 



presence of glucose; peptone utilized with 
difficult}'. 

Litmus milk: Becoming clearer in 10 to 
14 days. 

Potato: Glossy, barely visible, slimy to 
wrinkled; may become yellowish, brownish 
.yellow or chocolate-brown. 

The organism fixes atmospheric nitrogen 
and gives off CO2, utilizing glucose and 
sucrose. Other generally used carbon com- 
pounds are fructose, maltose, mannitol, 
inulin, dextrin, galactose, arabinose, starch, 
glycerol, ethyl alcohol, acetate, butyrate, 
citrate, lactate, malate, propionate and 
succinate. 

Nitrate : Improves growth in amounts 
less than 1 gm per liter; greater amounts 
are toxic. 

Fixes nitrogen moderately actively. 

Chemical analysis: Four-day cultures 
grown upon mannitol agar, when dried, are 
found to contain less than 0.5 per cent of 
hemicelluloses, less than 20 per cent of crude 
protein, less than 5 per cent of ash, and 
more than 30 per cent of lignin-like mate- 
rials (Greene, Soil Sci., 39, 1935, 327). The 
nitrogen fraction contains less than 1 per 



* Revised by Dr. A. W. Hofer, New York State Experiment Station, Cornell University, 
Geneva, New York, Jime, 1938; further revision by Dr. A. W. Hofer, May, 1954. 



284 



ORDER IV. EUBACTERIALES 



cent of amide nitrogen, less than 1 per cent 
of humin nitrogen and about 1 per cent of 
basic nitrogen. 

Aerobic. 

Optimum temperature, between 25° and 
28° C. 

Distinctive characters: Inability to grow 
in peptone media, even in the presence of 
glucose; frequent occurrence of a dark brown 
or black pigment. 

Source: Isolated from soil. 

Habitat : Occurs naturally in the majority 
of neutral or alkaline field soils. 

2. Azotobacter agilis Beijerinck, 1901. 
(Cent. f. Bakt., II Abt., 7, 1901, 577.) 

a'gi.lis. L. adj. agilis quick, agile. 

Rods, 4 to 6 microns in length, almost 
spherical. Actively motile by means of 
numerous, peritrichous flagella (Hofer, 
Jour. Bact., 47, 1944, 415). Some strains 
are reported to be non-motile. Gram-nega- 
tive. 

Grows in absence of organic nitrogen. 

Gelatin: No liquefaction. 

Mannitol agar colonies: Circular, gray- 
ish white, translucent with whitish center. 

Washed agar colonies : Show slight bluish 
green fluorescence. The presence of a fluo- 
rescent pigment is readily demonstrated 
by placing cultures under ultraviolet light, 
3600 A. Examination by paper chromotog- 
raphy indicates that this pigment is not 
fluorescin, the pigment found in fluorescent 
pseudomonads (Johnstone, Jour. Bact., 
69, 1955, 481). 

Mannitol agar slant: Grayish, translu- 
cent, fluorescent. 

Plain agar slant : Yellowish white, smooth, 
glistening, translucent with opaque center. 

Broth: Turbid, with sediment. 

Litmus milk: Becoming clear in 10 to 14 
days. 

Potato: Yellowish white, slimy, becom- 
ing yellowish brown. 

In the presence of organic acids, a green- 
ish or reddish pigment is formed. 

The organism fixes atmospheric nitrogen 
actively and gives off CO2 . 

Aerobic. 

Chemical analysis: Four-day cultures 
grown upon mannitol agar, when dried, con- 



tain more than 4 per cent of hemicelluloses, 
more than 45 per cent of crude protein, more 
than 7 per cent of ash, and less than 4 per 
cent of lignin-Iike materials. The nitrogen 
fraction contains more than 1 per cent 
amide nitrogen, more than 1 per cent humin 
nitrogen, and 2 per cent or more of basic 
nitrogen (Greene, Soil Sci., 39, 1935, 327). 

Optimum temperature, between 25° and 
28° C. 

Distinctive characters: Lack of a brown 
pigment; occasional fluorescence; growth 
in peptone broth containing glucose. 

Comment: A non-chromogenic variety 
of this species has been recognized by 
Kluyver and van den Bout (Arch. f. Mi- 
krobiol., 7, 1936,263). 

Source: Originally isolated from canal 
water at Delft. 

Habitat: Occurs in water and soil. 

3. Azolobacter indicus Starkey and De, 
1939. {Azotobacter iniicum (sic) Starkey and 
De, Soil Sci., 47, 1939, 337.) 

in'di.cum. L. adj. indicus of India. 

Ellipsoidal rods, 0.5 to 1.2 by 1 7 to 2.7 
microns when grown on nitrogen-free glu- 
cose agar. One of the distinctive character- 
istics is the presence of two large, round, 
highly refractive bodies in the cells, one 
usually at each end. Motile by means of 
numerous peritrichous flagella (Hofer, Jour. 
Bact., 47, 1944, 415). Gram-negative. 

The organism grows slowly but in time 
produces large amounts of slime. Has high 
acid tolerance, since it grows from pH 3 to 9. 

Sucrose or glucose agar plates: Colonies 
are colorless, round, very much raised and 
uniformly turbid, having much the appear- 
ance of heavy starch paste. After two weeks, 
a buff to light brown color develops. 

Mannitol agar slant: Grows very poorly. 

Peptone agar slant with 0.5 per cent glu- 
cose: Limited grayish growth. 

Nutrient broth: No growth. 

Liquid media: Generallj^ turbid with 
some sediment. 

Fixes atmospheric nitrogen readily with 
either glucose or sucrose as source of energy. 

Aerobic. 

Optimum temperature, 30° C. 



FAMILY I. AZOTOBACTERACEAE 285 

Distinctive characters: Tolerance of acid- because the organisms in the new genus 

ity; wide limits of pH tolerated; abundant differ in morphology and physiology in 

slime production; large globules of f;it important respects from the organisms in 

within cells. the genus Azotobacier proper. Further 

Relationships to other species: Derx comparative studies should be made before 

(Kon. Nederl. Akad. v. Wetensch., Amster- this separation is accepted, 

dam, Proc. Sect. Sci., 53, 1950, 145; Ann. Source: Isolated from soils of India and 

Bogoriensis, 1, 1950, 1) has made this species Java, 

the type species of a new genus, Beijerinckia, Habitat : Soils. 



FAMILY II. RHIZOBIACEAE CONN, 1938. 
(Jour. Bact., 36, 1938, 321.) 

Rhi.zo.bi.a'ce.ae. M.L. neut.n. lihizobium type genus of the family; -aceae ending to 
denote a family; M.L. fem.pl.n. Rhizohiaceae the Rhizobium family. 

Cells without endospores, rod-shaped, sparsely flagellated (one polar or lateral flagellum 
or 2 to 4 peritrichous ones); some species are non-motile. Usually Gram-negative. One 
genus {Chromobacterium) produces a violet pigment. Grow aerobically on ordinary culture 
media containing glucose. Glucose and sometimes other carbohydrates are utilized without 
appreciable acid formation. Saprophytes, symbionts and pathogens; the latter are usually 
plant pathogens forming abnormal growths on roots and stems. 

Key to genera of family Rhizobiaceae. 

I. Cells capable of fixing free nitrogen when growing symbiotically on the roots of Legu- 
minosae. 

Genus I. Rhizobium, p. 285. 
II. Either plant pathogens which attack roots or produce hypertrophies on stems or free- 
living non-chromogenic soil or water forms. Do not fix nitrogen. 

Genus II. Agrobaderiujn, p. 288. 
III. Usually free-living soil and water forms which produce a violet chromogenesis. 

Genus III. Chromobacterium, p. 292. 

Genus I. Rhizobium Frank, 1889.* 

(Phytomyxa Schroeter, in Cohn, Kryptogamen-Flora von Schlesien, 3, 1886, 134; Frank, 
Ber. d. deutsch. bot. Gesellsch., 7, 1889, 380.) 

Rhi.zo'bi.um. Gr. noun rhiza a root; Gr. noun bins life; M.L. neut.n. Rhizobium that 
which lives in a root. 

Rods which measure 0.5 to 0.9 bj^ 1.2 to 3.0 microns. Motile when young, commonly chang- 
ing to bacteroidal forms (a) upon artificial culture media containing alkaloids or glucosides, 
or in which aciditj^ is increased, or (b) during symbiosis within the nodule. Gram-negative. 
Aerobic. Heterotrophic, growing best with extracts of yeast, malt or other plant materials. 
Nitrites may be produced from nitrates. Nitrites are not utilized. Gelatin is not liquefied 
or is very slightly liquefied after long incubation. Optimum temperature, 25° C. This group 
is capable of producing nodules on the roots of Leguminosae and of fixing free nitrogen during 
this symbiosis. 

The type species is Rhizobium leguminosarum Frank. 

*Original revision by Dr. and Mrs. O. N. Allen, Universit}^ of Wisconsin, Madison, Wis- 
consin, January, 1938; further revision by Dr. O. N. Allen, September, 1953. 



286 ORDER IV. EUBACTERIALES 

Key to the species of genus Rhizobiuni. 
I. Litmus milk alkaline. 

A. Forms a serum zone in milk. Young cells peritrichous. 

1. Causes formation of root nodules on species of the genera Lathyrus, Pisum, Vicia 
and Lens. Bacteroids irregular with x-, y-, star- and club-shaped forms. 

1. Rhizohium leguminosarum. 

2. Causes formation of root nodules on Phaseolus vulgaris, P. muUiflorvs and P. 
angustifolius . Bacteroids, vacuolated rods, few branched forms. 

2. Rhizohium phaseoli. 

3. Causes formation of nodules on species in the genus Tri folium. Bacteroids pear- 
shaped, swollen, vacuolated. Pentoses usually not fermented. 

3. Rhizohitim trifolii. 

B. No serum zone formed in milk. Monotrichous cells usually occur; in some cases all 
motile cells are monotrichous. 

1. Causes formation of nodules on species of the genus Lupinus and on Ornithopus 
sativus. Bacteroids vacuolated, rods seldom branched. 

4. Rhizohium lupini. 

2. Causes formation of nodules on Soja max. Bacteroids long, slender rods, seldom 
vacuolated or branched. 

5. Rhizohium japonicum.* 

II. Litmus milk acid. Forms a serum zone in milk. Causes formation of root nodules on spe- 
cies of the genera Melilotus, Medicago and Trigonella. Bacteroids club-shaped, branched. 
Young cells peritrichous. 

6. Rhizohium meliloti. 

1. Rhizohium leguminosarum Frank, Slight acid production from glucose, ga- 

1890, emend. Baldwin and Fred, 1929. lactose, mannose, lactose and maltose. 
(Frank, Landwirtschaftliche Jahrbiicher, Aerobic. 

79, 1890, 563; Baldwin and Fred, Jour. Bact., Optimum temperature, 25° C. 

17, 1929, 146.) Source: Isolated from root nodules on 

le.gu.mi.no.sa'rum. M.L. fern. pi. n. Le- Lathyrus, Pisum (pea), Vicia (vetch) and 

guminosae old family name of the legumes; Lens (lentil). 

M.L. fern. pi. gen. n. leguminosarum of leg- Habitat: Widely distributed in soils where 

umes. the above-mentioned legumes are grown. 

Rods, 0.5 to 0.9 by 1.2 to 3.0 microns. Mo- 
tile by means of peritrichous flagella. Bac- 2. Rhizohium phaseoli Dangeard, 1926. 

teroids commonly irregular with x-, y-, (Le Botaniste, S^r. 16, 1926, 197.) 
star- and club-shaped forms. Vacuolate pha.se'o.li. Gr. noun phaselus the kidney 

forms predominate. Gram-negative. bean; L. noun phaseolus the kidney bean; 

Growth on mannitol agar is rapid, with M.L. mas.n. Phaseolus generic name of the 

tendency to spread. Streak is raised, glis- bean; M.L. gen . noun phaseoli of Phaseolus. 
tening, semi-translucent, white, slimy and Rods. Motile by means of peritrichous 

occasionally viscous. Considerable gum is flagella. Bacteroids are usually rod-shaped, 

formed. often vacuolated with few branched forms. 

* No specific name has been proposed for the organism causing the formation of nodules 
on plants that are members of the so-called "cowpea" group. Data showing possible inter- 
relationships of certain plant species of the soybean and cowpea cross-inoculation groups 
prompted Walker and Brown (Soil Science, 89, 1935, 221-225) to propose a consolidation 
of the two groups to be recognized as being inoculated by a single species, Rhizohium ja- 
ponicum. Results obtained by Reid and Baldwin (Proc. Soil Sci. Soc. Amer. for 1936, 1, 
1937, 219) show these inter-relationships to include the lupine group also. 



FAMILY II. RHIZOBIACEAE 



287 



Usually smaller than in Rhizobium legumi- 
nosarum and R. trifolii. Gram-negative. 

Growth on mannitol agar is rapid with 
tendency to spread. Streak inoculation is 
raised, glistening, semi-translucent, white, 
slimy. Occasionally mucilaginous, but this 
character is not so marked as in Rhizobinni 
trifolii. 

Very slight acid formation from glucose, 
galactose, mannose, sucro.'^e and lactose. 

Aerobic. 

Optimum temperature, 25° C. 

Source: Isolated from root nodules of 
Phaseolus vulgaris (kidney bean), P. angusti- 
folius (bean) and P. multiflorus (scarlet 
runner) (Burrill and Hansen, 111. Agr. Exp. 
Sta. Bui. 202, 1917, 137). 

Habitat: Widely distributed in the soils 
In which beans are grown. 

3. Rhizobium trifolii Dangeard, 1926. 
(Le Botaniste, Ser. 16, 1926, 191.) 

tri.fo'li.i. L. noun trifoliuni clover, tre- 
foil; M.L. neut.n. Trifolium generic name 
of clover; M.L. gen. noun trifolii of clover. 

Rods. Motile by means of peritrichous 
flagella. Bacteroids from nodules are pear- 
shaped, swollen and vacuolated, rarely x- 
or y-shaped. Gram-negative. 

Growth on mannitol agar is rapid. The 
colonies are white becoming turbid with 
age. Frequently mucilaginous. Streak cul- 
tures transparent at first. Growth mucilagi- 
nous, later flowing down the agar slant and 
accumulating as a slimy mass at the bottom. 
Produces large amounts of gum. 

Slight acid production from glucose, ga- 
lactose, mannose, lactose and maltose. 

Aerobic. 

Optimum temperature, 25° C. 

Source: Isolated from root nodules of 
species of Trifolium (clover). 

Habitat: Widely distributed in the soils 
where clover grows. 

4. Rhizobium lupini (Schroeter, 1886) 
Eckhardt et al., 1931. {Phytomyxa lupini 
Schroeter, in Cohn, Kryptogamen-Flora 
von Schlesien, 3, I, 1886, 135; Eckhardt, 
Baldwin and Fred, Jour. Bact., 21, 1931, 
273.) 

lu.pi'ni. L. noun lupinus the lupine; M.L. 



mas.n. Lupinus generic name of lupine; 
M.L. gen. noun lupini of Lupinus. 

Rods. Motile by means of 1 to 4 flagella, 
usually 2 or 3. Bacteroids are vacuolate 
rods, seldom if ever branched. Gram-nega- 
tive. 

Growth on j-east water, mannitol agar is 
scant to moderate with alkaline reaction. 

Beef -peptone gelatin: Little growth with 
extremely slow liquefaction. 

On galactose an alkaline reaction serves 
to differentiate Rhizobium lupini from all 
fast-growing rhizobia (R. phaseoli, R. rneli- 
loti, R. trifolii and R. leguminosarum) . An 
initial alkaline reaction followed more 
quickly by an acid reaction on rhamnose 
and xylose separates R. lupini from slow- 
growing R. japonicum and the Rhizobium 
sp. from cowpea. 

In general Rhizobium lupini produces 
slight to moderate acidity on pentose sugars 
and no change or alkaline reaction on hex- 
oses, disaccharides or trisaccharides. 

Litmus milk: No serum zone; no reduc- 
tion; slight alkaline reaction. 

Meager growth on potato and parsnip 
slants and on carrot agar. 

Aerobic. 

Optimum temperature, 25° C. 

Source: Isolated from root nodules on 
Lupinus (lupine), Serradella and Orniihopus. 

Habitat: Widely distributed in soils in 
which these legumes grow. 

5. Rhizobium japonicum (Kirchner, 
1895) Buchanan, 1926. (Rhizobacterium ja- 
ponicum Kirchner, Beitrage z. Biol. d. Pflan- 
zen, 7, 1895, 213; Buchanan, Proc. Iowa 
Acad. Sci., 83, 1926, 81.) 

ja.po'ni.cum. M.L. adj. japonicus of 
Japan. 

Rods. Motile by means of monotrichous 
flagella. Bacteroids of nodules are long and 
slender with only occasional branched and 
swollen forms. Gram-negative. 

Growth on mannitol agar is slow and 
scant. The streak is slightly raised, glisten- 
ing, opaque, white, butyrous, with little 
gum formation. 

Pentose sugars give better growth than 
the he.xoses. 

Little if any acid formed from carbohy- 



288 ORDER IV. EUBACTERIALES 

drates. Acid slowly formed from xylose and Rods. Motile by means of peritrichous 

arabinose. flagella. Bacteroids club-shaped and 

Aerobic. branched. Gram-negative. 

Optimum temperature, 25° C. Growth on mannitol agar is fairly rapid. 

Source: Isolated from root nodules on The streak is raised, glistening, opaque, 

Soja max (soy bean). pearly white, butyrous. Considerable gum 

Habitat : Widely distributed in soils where is formed, 

soy beans are grown. Acid from glucose, galactose, mannose 

and sucrose. 

6. Rhizobium meliloti Dangeard, 1926. Aerobic. 

(Le Botaniste, Sdr. 16, 1926, 194.) Optimum temperature, 25° C. 

me.li.lo'ti. Gr. noun vieli honey; Gr. Source: Isolated from root nodules of 

noun lotus the lotus; Gr. noun melilotus Melilotus (sweet clover), Medicago and Tri- 

melilot or sweet clover; M.L. fem.n. Meli- gonella. 

lotus generic name of sweet clover; M.L. Habitat: Widely distributed in soils in 

gen. noun meliloti of Melilotus. which these legumes grow. 

Genus II. Agrobacterium Conn, 194^.* 
(Jour. Bact., U, 1942, 359.) 

Ag.ro. bac.te'ri.um. Gr. noun agrus a field; Gr. dim.neut.n. bacterium a small rod; M.L 
neut.n. Agrobacterium field rodlet or bacterium. 

Small, short rods which are typically motile by means of 1 to 4 peritrichous flagella (if 
only one flagellum, lateral attachment is as common as polar). Ordinarily Gram-nega- 
tive. On ordinary culture media they do not produce visible gas nor sufficient acid to be 
detectable by litmus. In synthetic media, enough CO2 may be produced to show acid with 
brom thymol blue or sometimes with brom cresol purple. Gelatin is either very slowly li- 
quefied or not at all. Free nitrogen cannot be fixed, but other inorganic forms of nitrogen (ni- 
trates or ammonium salts) can ordinarily be utilized. Optimum temperature, between 25° 
and 30°C. Found in soil, in plant roots in the soil or in the stems of plants where they pro- 
duce hypertrophies; occasionally from marine sources. 

The type species is Agrobacterium tumefaciens (Smith and Townsend) Conn. 

Key to the species of genus Agrobacterium. 

I. Plant pathogens. 

A. Nitrites produced from nitrates, sometimes only to a slight extent. 

1. Produce galls on angiosperms. 

a. Indole production slight. 

1. Agrobacterium tumefaciens. 
aa. Indole not produced. 

2. Agrobacteriiim gypsophilae. 

2. Produces galls on gymnosperms. 

3. Agrobacterium pseudotsugae. 

B. Nitrites not produced from nitrates. 

1. Pathogenic to apples. 

4. Agrobacterium rhizogenes. 

2. Pathogenic to raspberries and blackberries. 

5. Agrobacterium rubi. 

* Originally prepared by Prof. H. J. Conn, New York State Experiment Station, Cornell 
University, Geneva, New York, September, 1943; revised by Prof. Walter H. Burkholder, 
Cornell University, Ithaca, New York, July, 1954. 



FAMILY II. RHIZOBIACEAE 



289 



II. Not pathogenic to plants. 

A. From soil. Grows on potato. Nitrates completely assimilated; test for nitrites may 
be negative. 

6. Agrobacieriion radiohacter . 

B. From marine mud. Does not grow on potato. Nitrites produced from nitrates. 

7. Agrohacterium stellulatum. 



1. Agrobacteriuni tumefaciens (Smith 
and Townsend, 1907) Conn, 1942. {Bacterium 
tumefaciens Erw. Smith and Townsend, 
Science, 25 (N.S.), 1907, 672; Conn, Jour. 
Bact., 44, 1942, 359.) 

tu.me.fa'ci.ens. L. part. adj. tumefaciens 
tumor-producing. 

Description taken from Riker, Banfield, 
Wright, Keitt and Sagen (Jour. Agr. Res., 
41, 1930, 507), Sagen, Riker and Baldwin 
(Jour. Bact., £8, 1934, 571) and Hendrick- 
son, Baldwin and Riker (Jour. Bact., 28, 
1934, 597). 

Rods, 0.7 to 0.8 by 2.5 to 3.0 microns, oc- 
curring singly or in pairs. Encapsulated. 
Motile by means of 1 to 4 flagella. Gram- 
negative. 

Agar colonies: Small, white, circular, 
smooth, glistening, translucent, entire. 

Broth: Slightly turbid, with thin pellicle. 

Litmus milk: Slow coagulation. Litmus 
reduced. Neutral to alkaline. 

Indole production slight. 

Slight acid from glucose, fructose, arabi- 
nose, galactose, mannitol and salicin. 

Starch not hydroh^zed. 

Nitrites produced from nitrates to a very 
slight e.xtent. 

Optimum temperature, between 25° and 
28° C. 

Facultative anaerobe. 

Distinctive characters: Causes a gall 
formation, parenchymatous in character, 
which, because of its soft nature, is subject 
to injury and decay. 

Agrobacteriuni tumefaciens strongly ab- 
sorbs Congo red and aniline blue in contrast 
to little or no absorption by A. rhizogenes. 
A. tumefaciens makes abundant growth on 
sodium selenite agar and calcium glj'cero- 
phosphate medium with mannitol in con- 
trast to no growth or a very slight trace 
by A. rhizogenes (Hendrickson et al., loc. 
cit.). 

Comment: A variety of this species that 



causes galls on blueberry has been de- 
scribed by Demaree and Smith (Phyto- 
path., .^^, 1952, 88). 

Source: Isolated from galls on plants. 

Habitat: Causes galls on Paris daisy and 
is cross-inoculable on over 40 families. 



2. Agrobacteriuni gypsophilae (Brown, 
1934) Starr and Weiss, 1943. {Bacterium 
gypsophilae Brown, Jour. Agr. Res., 48, 
1934, 1109; Starr and Weiss, Phytopath., 
33, 1943, 316.) 

gyp.so'phi.lae. Gr. noun gypsus chalk; 
Gr. adj. philus loving; M.L. fem.n. Gyp- 
sophila chalk-lover, generic name; M.L. 
gen. noun gypsophilae of Gypsophila. 

Rods, 0.2 to 0.8 by 0.4 to 1.4 microns. Mo- 
tile by means of 1 to 4 flagella. Encapsu- 
lated. Gram-negative. 

Gelatin: Liquefaction slow, beginning 
after 1 month. 

Beef -infusion agar colonies: Circular, 
Naples-yellow, smooth or rough, butyrous. 

Broth: Turbid in 24 hours. 

Milk: Coagulation and peptonization. 

Indole not produced. 

Hydrogen sulfide: A trace may be pro- 
duced. 

Acid but no gas from glucose, sucrose, 
maltose, mannitol and glycerol. No acid 
from lactose. 

Starch not hydrolyzed. 

Nitrites produced from nitrates. 

Aerobic, facultative. 

Distinctive characters : Differs from Xan- 
ihomonas beticola in starch hydrolj^sis 
and hydrogen sulfide production; further- 
more, these two species cannot be cross- 
inoculated. 

Source: Isolated from several galls on 
Gypsophila. 

Habitat: Produces galls in Gypsophila 
paniculata and related plants. 



290 



ORDER IV. EUBACTERIALES 



3. Agrobacteriuni pseudotsugae (Han- 
sen and Smith, 1937) Savulescu, 1947. {Bac- 
terium pseudotsugae Hansen and R. E. 
Smith, Hilgardia, 10, 1937, 576; Savulescu, 
Anal. Acad. Romane, III, 22, 1947, 10.) 

pseu.do.tsu'gae. Gr. adj. pseudes false; 
Jap. noun tsuga an evergreen; M.L. fem.n. 
Tsuga generic name of hemlock; M.L. fem.n. 
Pseudotsuga false Tsuga, a generic name; 
M.L. gen. noun pseudotsugae of Pseudotsuga. 

Rods 0.5 to 1.5 by 1.9 to 3.9 microns. 
Probably motile; type of flagellation 
doubtful. Gram-negative. 

Gelatin: Liquefied. 

Nutrient agar slant: Growth scant, flat, 
glistening, smooth, translucent, whitish. 

Broth: Growth slight. No sediment. 

Milk: No acid. 

Hydrogen sulfide production slight. 

Acid but no gas from glucose, fructose, 
galactose and maltose. No acid or gas from 
lactose, sucrose or glycerol. 

Starch not hydrolyzed. 

Nitrites produced from nitrates. 

Facultative aerobe. 

Source: Isolated from galls on Douglas 
fir in California. 

Habitat: Pathogenic on Douglas fir, Pseii- 
dotsuga taxifolia. 

4. Agrobacterium rhizogenes (Riker et 
al., 1930) Conn, 1942. {Bacterium rhizo- 
genes Riker, Banfield, Wright, Keitt and 
Sagen, Jour. Agr. Res., 4^ , 1930, 536; 
Conn, Jour. Bact., U, 1942, 359.) 

rhi.zo'ge.nes. Gr. noun rhiza a root; Gr. 
V. genneo to produce; M.L. adj. rhizogenes 
root-producing. 

Rods, 0.4 by 1.4 microns, occurring singly. 
Motile by means of 1 to 4 flagella. Encap- 
sulated. Not acid-fast. Gram-negative. 

Gelatin: No liquefaction. 

Agar colonies: Circular, smooth, convex, 
finely granular; optical characters, trans- 
lucent through gray to almost white. 

Agar slant: Moderate, filiform, translu- 
cent, raised, smooth, slimy. 

Broth: Turbid, with heavy pellicle. 

Litmus milk: Acid, slow reduction. 

Indole not produced. 

Nitrites not produced from nitrates. 

Acid but no gas from arabinose, xylose, 
rhamnose, glucose, galactose, mannose, 



maltose, lactose, salicin and erythritol. No 
acid or gas from fructose, sucrose, raffinose, 
melezitose, starch, dextrin, inulin, aesculin, 
dulcitol or mannitol. 

Starch not hydrolyzed. 

Optimum temperature, between 20° and 
28° C. 

Aerobic. 

Distinctive characters: Agrobacterium 
rhizogenes differs from Agrobacterium tuvie- 
faciens by stimulating root formation in- 
stead of soft, parenchj'^matous crown galls. 
A. rhizogenes lacks the ability of A. tume- 
faciens to utilize simple nitrogenous com- 
pounds as KNO3 . A. rhizogenes absorbs 
congo red and brom thymol blue slightly 
and aniline blue not at all. Will not grow 
on sodium selenite agar (see A. tumefaciens 
for response to same materials). Does not 
infect tomato. 

Source : Isolated from hairy-root of apple 
and other plants. 

Habitat: Pathogenic on apple, etc. 

5. Agrobacterium rubi (Hildebrand, 
1940) Starr and Weiss, 1943. {Phyfomonas 
rubi Hildebrand, Jour. Agr. Res., 61, 1940, 
694; Starr and Weiss, Phytopath., 33, 1943, 
316.) 

ru'bi. L. noun rubus the blackberry; L. 
noun Rubus generic name of blackberry; 
L. gen. noun rid)i of Rubus. 

Rods, 0.6 by 1.7 microns, occurring singly, 
in pairs or in short chains. Motile by means 
of 1 to 4 flagella. Gram-negative. 

Gelatin: No liquefaction. 

Potato -mannitol -agar slants: Growth 
slow, moderate, filiform, white to creamy 
white, with butyrous consistency later be- 
coming leathery. 

Broth: Turbid in 36 to 48 hours. 

Milk: A slight serum zone; pink color; 
acid and curd formed. 

Hydrogen sulfide not produced. 

Indole not produced. 

Acid from glucose, d-galactose, d-man- 
nose, d-fructose, d-xylose, d-arabinose, 
sucrose and maltose. None from lactose 
(Pinckard, Jour. Agr. Res., 50, 1935, 933). 

Starch not hydrolyzed. 

Nitrites not produced from nitrates. 

Ferric ammonium citrate, uric acid, ox- 
amide, succinimide, 1-asparagine, 1-tyro- 



FAMILY II. RHIZOBIACEAE 



291 



sine, 1-cystine, d-glutamic acid and yeast 
extract can be used as a source of nitrogen 
(Pinckard, loc. cit.). 

Temperature relations: Optimum, 28° C. 
Minimum, 8° C. Maximum, 36° C. (Pinck- 
ard, loc. cit.). 

Distinctive characters: Differs from Agro- 
bacterium tumefaciens in that it does not 
utilize nitrates and grows much more slowly 
on ordinary media. Infects only members 
of the genus Rubus. Starr and Weiss (Phyto- 
path., 33, 1943, 317) state that this species, 
unlike Agrobacterium tumefaciens and Agro- 
bacterium rhizogenes, does not utilize as- 
paragin as a sole source of carbon and nitro- 
gen. 

Source: Isolated from raspberry canes, 
Rubus spp. 

Habitat: Pathogenic on black and purple 
cane raspberries, on blackberries and, to a 
lesser extent, on red raspberries. 

6. Agrobacleriuni radiobacter (Bei- 

jerinck and van Delden, 1902) Conn, 1942. 
{Bacillus radiobacter Beijerinck and van 
Delden, Cent. f. Bakt., II Abt., 9, 1902, 3; 
Conn. Jour. Bact., 44, 1942, 359.) 

ra.di.o.bac'ter. L. noun radius a ray, 
beam; M.L. bacter masculine equivalent of 
Gr. neut.n. bactrum a rod or staff; M.L. 
mas.n. radiobacter ray rod. 

Small rods, 0.15 to 0.75 by 0.3 to 2.3 mi- 
crons, occurring singly, in pairs and, under 
certain conditions, in star-shaped clusters. 
Motile with one to four flagella. Prevail- 
ingly Gram-negative, but an occasional 
culture is variable. 

Nutrient gelatin stab: No liquefaction. 

Agar slant: Flat, whitish slimy layer. 

Mannitol - calcium - glycerophosphate agar 
streak plates: Abundant, raised, slimy 
growth surrounded by a brown halo w'ith 
an outer zone of white precipitate (Riker 
et al.. Jour. Agr. Res., 41, 1930, 524). 

Broth: Turbid; heavy ring or pellicle if 
veal infusion is present. 

Litmus milk: Serum zone with pellicle 
in one week; usually turns a chocolate- 
brown in 2 weeks; same in plain milk, but 
with less browning. 

Potato: Raised slimy mass becoming 
brownish; potato may be browned. 

Starch not hydrolj'zed. 



No organic acid or visible gas from sugars ; 
nearly all sugars, glycerol and mannitol 
are utilized with the production of CO 2. 

Nitrates completely assimilated; test for 
nitrites may be negative (Hofer, Jour. Bact., 
41, 1941, 202). 

Temperature relations: Optimum, 28° C. 
Minimum, near 1° C. Maximum, 45° C. 

Aerobic. 

Media containing KNO3, K2HPO4 and 
glycerol, ethanol or propanol become alka- 
line to phenol red (Sagen, Riker and Bald- 
win, Jour. Bact., 28, 1934, 581). 

Growth occurs in special alkaline media 
of pH 11.0 to 12.0 (Hofer, Jour. Amer. Soc. 
Agron., 27, 1935, 228). 

Hydrogen sulfide produced if grown in 
ZoBell and Feltham's medium (ZoBell and 
Feltham, Jour. Bact., 28, 1934, 169). 

Distinctive characters: Browning of man- 
nitol-calcium-glycerophosphate agar; in- 
ability to cause plant disease or to produce 
nodules on roots of legumes; complete uti- 
lization of nitrate (the nitrate disappears) 
in the peptone-salt medium of Riker et al. 
(Riker et al., Jour. Agr. Res., 4I, 1930, 529) 
and failure to absorb congo red (Riker et 
al., ibid., 528). 

This species bears at least superficial 
resemblances to certain Rhizobium spp. 
but may be distinguished from them by 
the first two characters listed above and 
by the following in addition: Growth at a 
reaction of pH 11 to 12; heavy ring or pel- 
licle formation on veal infusion broth; hy- 
drogen sulfide production in the mannitol - 
tryptone medium of ZoBell and Feltham 
(ZoBell and Feltham, op. cit., 1934, 169); 
production of milky white precipitate on 
nitrate-glycerol-soil-extract agar. 

Source: Isolated from soil. 

Habitat: Soil around the roots of plants, 
especially legumes. 

7. Agrobacterium stellulatum Stapp 
and Knosel, 1954. (Zent. f. Bakt., II Abt., 
108, 1954, 244.) 

stel.lu.la'tum. L. noun stella star; M.L. 
adj. stellulatus resembling a small star. 

Rods, 0.2 to 0.8 by 0.3 to 2.1 microns, oc- 
curring singly or in pairs; in certain media, 
star-like clusters are found. Motile by means 



292 ORDER IV. EUBACTERIALES 

of a single, polar flagellum. Not acid-fast. Litmus milk : Slight growth with a neutral 

Gram-negative. to alkaline reaction; litmus slowly decolor- 

Gelatin: No liquefaction. ized; no peptonization. 

Peptone agar colonies: Small, round. Potato: No growth, 

smooth, gray, glistening. Indole not produced. 

Peptone agar slant: Growth is poor, Nitrites produced from nitrates, 

widely spread, colorless to whitish, trans- Congo red is weakly absorbed, 

lucent and resembles droplets of moisture. No growth at pH 4.5. 

Mannitol- calcium- glycerophosphate agar Optimum temperature, between 15° and 

slant: Weak growth resembling a film of 25° C. 

droplets of moisture. Distinctive characters: May be distin- 

Broth: Slightly turbid; no pellicle; very ^^j^j^^^ ^^^^^ Agrohacterium radiohacter 

small sediment. j * , j- ■ ^ ^ j^i 

r, xi -x, T'Tv-/^ A • 1 X 11 1 ^^^ ^- tumejaciens by weak growth on 

Broth with KInOs: Acid toward phenol , -,1 i -n i r • x 

, bouillon or bouillon agar, by forming star- 

Q^o +^.. r.A- ^. 001A \KT 1 +1, like clusters on sea-water medium 2216, 

Sea-water medium 221b: Weak growth; . ' 



good formation of star-shaped clusters. 



by weak growth on calcium-glycerophos- 



Carrot agar: Very weak growth. P^^^^ ^^ar, by weak absorption of Congo 

Iron-manganese-carrot juice: Very weak ^'^d, by failure to grow on potato, by very 

development; no surface growth; no star- weak growth on carrot agar or Fe-Mn-carrot 

shaped clusters. juice and by forming star-like clusters on 

Iron -manganese -sea water-carrot juice: Fe-Mn-sea water-carrot juice. 

Good growth; thin, easily destroyed, sur- Source: Isolated from marine mud. 

face film; no star-shaped clusters. Habitat: Marine sources. 

Genus III. Chromobacteriuni Bergonzini, 1881.* 

(Cromobacterium (sic) Bergonzini, Ann. Societa d. Naturalisti in Modena, Ser. 2, 
14, 1881, 153.) 

Chro.mo.bac.te'ri.um. Gr. noun chroma color; Gr. noun bacterium a small rod; M.L. 
neut.n. Chromobacteriuni colored rod. 

Rods which measure 0.4 to 0.8 by 1.0 to 5.0 microns. Motile by means of 1 to 4 or more 
flagella. Gram-negative. A violet pigment (violacein) is produced which is soluble in alcohol 
but not in water or chloroform. Grow on ordinary culture media, usuallj^ forming acid from 
glucose, sometimes from maltose and sucrose, but not from lactose. Gelatin is liquefied, 
sometimes slowly. Indole is not produced. Nitrites usually produced from nitrates; the 
nitrites are frequently further reduced to nitrogen and possibly nitrous oxide. Some strains 
grow well at 4° C. while others grow well at 37° C. with a maximum temperature of between 
40° and 42° C. ; none grow at both 4° and 37° C. Usually saprophytic soil and water bacteria. 
Occasionally pathogenic to animals and man. 

The type species is Chromobacierium violaceum (Schroeter) Bergonzini. 

Discussion: The most characteristic feature of this group is its production of a violet 
pigment. The chemistry of this pigment has been well worked out by Tobie (Bull. Assoc. 
Diplomes Microbiol., Fac. Pharm. de Nancy, No. 18, 1939, 7). Since violacein appears to be 
chemically related to indigo, peritrichous organisms producing the latter pigment may 
tentatively be placed in this genus pending further study (Tobie, Jour. Bact., 35, 1938, 11). 
Cultures of violet bacteria are difficult to maintain in culture collections and are frequently 

* Prepared by Prof. Robert S. Breed, New York State Experiment Station, Cornell Uni- 
versity, Geneva, New York, from Cruess-Callaghan and Gorman, Scientific Proc. Royal 
Dublin Society, 21, 1935, 213, in January, 1938; further revision, July, 1955, with the as- 
sistance of Dr. Ethel T. Eltinge, Mount Holyoke College, South Hadley, Massachusetts, 
and Dr. W. C. Tobie, Old Greenwich, Connecticut. 



FAMILY II. RHIZOBIACEAE 293 

lost (Sneath, Jour. Gen. Microbiol., 13, 1955, p. I, has recently reported that these organ- 
isms are highly sensitive to traces of hydrogen peroxide in the medium). They have a ten- 
dency to produce mucous, gummy, gelatinous or even leather^' growths (Corpe, Jour. Bact., 
65,1953,470). 

The separation of the true violet chromogens into three species is in accord with the 
recommendations of Cruess-Callaghan and Gorman (Sci. Proc. Royal Dublin Soc, 21, 
1938, 213). Their conclusions were based on a study of 18 named cultures from culture col- 
lections and 6 freshly isolated cultures. Others have studied this same problem. For ex- 
ample, Hans and Bicknell (Bact. Proc. 53rd Gen. Meeting Soc. Amer. Bact., San Francisco, 
1953, 33) agree that only a few species should be recognized. Eltinge (personal communica- 
tion, Sept., 1955), after a study of a collection of 88 cultures, reports that the group may 
readily be separated into cultures that will grow at 4° but not at 37° C. and cultures that 
will not grow at 4° but do grow at 37° to 42° C. This seems to be one of the most constant 
of the differences in characters, and it is used in the classification drawn up by Cruess-Cal- 
laghan and Gorman. 

There is a partial correlation between the growth-temperature relationships and the 
ability to reduce nitrate (Eltinge, Antonie van Leeuwenhoek, £2, 1956, 139). Some cultures 
(Chromobacterium violaceum) that may give a negative test for nitrite production actually 
reduce the nitrate so rapidly with the production of free gas that they have sometimes 
been reported in the literature as failing to reduce nitrate. Other cultures merely reduce 
the nitrate to nitrite (Chromobacterium janthinum) , while still other cultures do not attack 
nitrate at all. 

Corpe (Jour. Bact., 62, 1951, 515) found that he could readily isolate these organisms by 
adding sterile rice grains to moistened soil. The latter observation confirms an earlier ob- 
servation by Beijerinck (Folia Microbiologica, 4, 1916, 207) who added wheat bran or fibrin 
to tap-water infusions in order to develop these violet bacteria. Starchy substances appear 
to stimulate growth, as all grow abundantly on potato with a yellow growth that usually 
turns to a dark violet or purple. 

A number of organisms have been classed as species of Chromobacterium because they 
develop a bluish chromogenesis without regard to the fact that their pigments are not chem- 
ically the same as violacein. The majority of these cultures are polar flagellate and have 
been shown to belong to the genus Pseudomonas. Frequently these blue pigments are water- 
soluble and have a tendencj^ to become rose-colored. 

The violet organisms differ in important respects from the organisms placed in Serratia. 
The latter produce prodigiosin and belong with the coliform group. The violet organisms 
show the same type of gummy colony growth that is characteristic of many of the species 
found in Rhizobiaceae , their carbohydrate metabolism is like that of the species in this fam- 
ily, and they possess the same unusual type of monotrichous to peritrichous flagellation. 
The position of the violet bacteria in the family Rhizobiaceae appears to be a natural one. 

In recent j^ears these violet bacteria have been found in fatal septicemias in man and 
animals (see Sippel, Medina and Atwood, (good bibliography). Jour. Amer. Vet. Med. 
Assoc, 124, 1954, 467; Audebaud, Ganzin, Ceccaldi and Merveille, Ann. Inst. Past., 87, 1954, 
413; and Black and Shahan, Jour. Amer. Med. Assoc, 110, 1938, 1270). These pathogenic 
organisms have frequently been identified as Chromobacterium violaceum Bergonzini be- 
cause they produce a violet pigmentation. However, by definition, this species does not 
grow at 37° C. In the early literature C. janthinum Zopf was sometimes regarded as a sepa- 
rate species, while in other cases C. violaceum and C. janthinuvi were regarded as identical. 
Inasmuch as both Schroeter and Bergonzini, the investigators who first described C. vio- 
laceum, grew their organisms at room temperature, and inasmuch as descriptions list them 
as growing at room temperature while C. janthinum is normally described as growing best at 
room temperature, Cruess-Callaghan and Gorman emended the descriptions of these two 
species in such a way as to make C. violaceum the organism which will not grow at 37° C. 
while they describe C. janthinum as growing at 37° C. In view of these emended descrip- 



294 



ORDER IV. EUBACTERIALES 



tions, the violet organisms isolated from warm-blooded animals should be identified as 
C. janthinum not as C. violaceum. 

Key to the species of genus Chroniobacteriiim. 

I. Fresh-water and soil organisms that produce a violet chromogenesis. 

A. No growth at 37° C. 

1. Gelatin stab may show violet ring or pellicle. 

1. Chromohacterium violaceum. 

2. Gelatin stab develops heavy membranous growth on liquefied gelatin. Usually 
violet in color. 

2. Chromohacteniivi amethystinum. 

B. Growth at 37° C. 

3. Chromohacterium janthinum. 

II. Optimum growth in media containing 12 per cent salt. Chromogenesis bluish to blue- 
brown or yellowish. 

4. Chromohacterium marismortui. 



1. Chroniobacterium violaceum 

(Schroeter, 1872) Bergonzini, 1881. {Bac- 
teridium violaceum Schroeter, Beitrage z. 
Biol. d. Pflanzen, 1, Heft 2, 1872, 126; Cro- 
mobacterium violaceum (sic) Bergonzini, 
Ann. Societa d. Naturalist! in Modena, 
Ser. 2, 14, 1881, 153.) 

vi.o.la'ce.um. L. adj. violaceus violet- 
colored. 

Slender rods, 0.8 to 1.0 by 2.0 to 5.0 mi- 
crons, occurring singlj^ and in chains. Mo- 
tile, usually by means of a single flagellum, 
but some cells show several flagella arranged 
peritrichously. Gram-negative. 

Gelatin colonies: Circular, gray, entire, 
sometimes with a violet center. 

Gelatin stab: Infundibuliform liquefac- 
tion, sometimes with violet ring or pellicle 
and sediment. 

Agar colonies: Whitish, fiat, glistening, 
moist, becoming violet. 

Agar slant: Violet, moist, sometimes 
gummy, shiny, spreading growth. 

Broth: Slightly turbid; violet ring; granu- 
lar to viscid sediment. 

Litmus milk: Violet ring or pellicle. Di- 
gestion slow. Alkaline. 

Potato: Growth yellow to dark violet. 

Loffier's blood serum: Slow liquefaction. 

Indole not produced. 

Acid from glucose and usually from mal- 
tose and sucrose. No acid from lactose. 

Nitrites produced from nitrates and fre- 
quently reduced further to a gas (N2). 

Aerobic, facultative. 



Temperature relations: Optimum, be- 
tween 25° and 30° C. Slight growth between 
2° and 4° C. No growth at 37° C. 

Source: Isolated from slices of cooked 
potato which had been exposed to air con- 
tamination and then incubated at room 
temperature. 

Habitat: Soil and water. 

2. Chroniobacterium amethystinvim 

(Chester, 1897) Holland, 1920. (Bacillus 
membranaceus amethystinus Eisenberg, Bakt. 
Diag., 1891, 421; Bacterium amethystinus 
(sic) Chester, Ann. Rept. Del. Col. Agr. 
Exp. Sta., 9, 1897, 117; Holland, Jour. Bact., 
5, 1920, 222.) 

a.me.thj^s'ti.num. Gr. adj. amethystinus 
of amethyst. 

Rods, 0.5 to 0.8 by 1.0 to 1.4 microns, 
occurring singly. Motile with a single or 
occasionally with peritrichous flagella. 
Gram-negative. 

Gelatin colonies: Thin, bluish, becoming 
violet, crumpled. 

Gelatin stab: Heavy, violet-black pel- 
licle. Liquefied. 

Agar colonies : Deep violet, surface rugose. 

Agar slant: Thick, moist, gummy, rugose, 
yellowish white growth, becoming violet 
sometimes with a metallic luster. 

Broth: Pellicle; violet sediment; fluid 
becoming violet. 

Litmus milk: Violet pellicle. Digestion 
turning alkaline. 



FAMILY II. RHIZOBIACEAE 



295 



Potato: Yellow to deep violet, rugose, 
spreading growth. 

Indole not produced. 

Usually no acid from glucose, maltose or 
sucrose. No acid from lactose. 

Nitrites produced from nitrates. 

Aerobic, facultative. 

Temperature relations: Optimum, 30° C. 
Good growth in 7 days between 2° and 4° C. 
No growth at 37° C. 

Comment: The most characteristic fea- 
ture of the original culture of this species 
was its ability to grow a heavy, folded, mem- 
branous pellicle on gelatin stabs and other 
media. The original culture also sometimes 
produced a metallic sheen. If the descrip- 
tions of all of the cultures regarded by 
Cruess-Callaghan and Gorman (Scientific 
Proc. Royal Dublin Soc, 21, 1935, 219) as 
C. amethystinum are taken into account, 
there really are no other important charac- 
ters by which this species can be separated 
from C. violaceum. Moreover, those that 
have studied many cultures of these violet 
organisms over a long period of time, with 
replatings to purify, report that this mem- 
branous growth may develop on almost 
any subculture of typical C. violaceum. The 
formation of this heavy, folded growth 
should therefore probably be regarded as a 
dissociation phenomenon. Further com- 
parative studies will presumably show that 
C. amethystinum should be regarded as a 
variant form of C. violaceum. 

Source: Isolated once by Jolles from 
spring water from Spalato. 

Habitat: Water. 

3. Chroniobacterium janthinuni 

(Zopf , 1883) Holland, 1920. {Bacterium jan- 
thinum Zopf, Die Spaltpilze, 1 Aufl., 1883, 
68; Holland, Jour. Bact., 5, 1920, 222.) 

jan'thi.num. Gr. adj. janthinus violet- 
colored. 

Rods, 0.5 to 0.8 by 1.5 to 5.0 microns, 
occurring singly. Motile with peritrichous 
flagella. Gram-negative. 

Gelatin colonies: Circular, yellow, be- 
coming violet. 

Gelatin stab: White to violet surface 
growth. Infundibuliform liquefaction. 

Agar colonies: Creamy center, violet 
margin. 



Agar slant: Yellowish, moist, gummy, 
glistening growth becoming deep violet. 

Broth: Turbid, with light violet pellicle. 

Litmus milk: Violet cream layer. Litmus 
decolorized from below. Rapid digestion. 

Potato: Violet to violet-black, spreading 
growth. 

Indole not produced. 

Acid from glucose. No acid from maltose, 
lactose or sucrose. 

Nitrites generally produced from nitrates. 

Aerobic, facultative. 

Temperature relations: Optimum, 30° C. 
No growth between 2° and 4° C. Grows well 
at 37° C. 

Source: Isolated from pieces of pig's blad- 
der floating on badly contaminated water. 

Habitat: Water and soil. This appears 
to be the species that causes a fatal septi- 
cemia in animals and man. 

4. Chromobacterium niarismortui 

Elazari-Volcani, 1940. (Studies on the Mi- 
croflora of the Dead Sea. Thesis, Hebrew 
Univ., Jerusalem, 1940, VII and 76.) 

ma.ris.mor'tu.i. L. noun mare the sea; 
L. gen . noun maris of the sea; L. adj . mortuus 
dead; M.L. gen. noun marismortui of the 
Dead Sea. 

Rods, the length of which varies greatly 
with the concentration of salt and media. 
On agar media, in 3 to 24 per cent salt, the 
cells are usually 0.5 by 1.3 to 3.0 microns; 
in liquid media, 4.5 to 13.0 microns. Occur 
singly and in pairs. In 0.5 and 30 per cent 
salt and in Dead Sea water, the cells are 
usually very long, twisted threads. Motile 
by means of 4 to 6 peritrichous flagella. 
Gram-negative. 

Gelatin stab (12 per cent salt-1 per cent 
proteose peptone-15 per cent gelatin) : Fili- 
form, blue-brown, nailhead surface growth. 
Very slight infundibuliform liquefaction 
after six weeks. 

Agar colonies (12 per cent salt-1 per cent 
proteose peptone-2 per cent KNO3) : Circu- 
lar, smooth, entire, slightly convex and 
concentrically ringed with dark brown cen- 
ters followed by blue-brown, gray-brown 
and yellow rings and a colorless transparent 
margin. On removing the colony, a print 
remains in the agar consisting of three 
zones : a blue center, a brownish gray inner 



296 ORDER IV. EUBACTERIALES 

ring and a blue outer ring. Colonies colored Acid without gas from glucose, galactose, 

only when well separated and at an optimum maltose, lactose, arabinose and xjdose. 

salt concentration of 12 per cent. Starch not hydrolyzed. 

Agar slant (12 per cent salt-1 per cent Nitrites produced from nitrates; no gas 

proteose peptone-2 per cent KNO3) : Moder- is produced, 

ate, filiform, slightly raised, smooth, Aerobic. 

slightly transparent growth with a blue- Optimum temperature, 30° C. 

brown margin; leaves a colored print in Salt tolerance: Halotolerant, growing in 

the agar. 0.5 to 30 per cent salt and in Dead Sea water. 

Broth (12 per cent salt-1 per cent pep- Optimum growth at 12 per cent salt, 

tone): Very turbid; w*hite pellicle; broth Source: Isolated from the water of the 

turns brown, the color disappearing after Dead Sea. 

several days. Habitat: Found in places where the salt 

Indole not produced. content of water is high. 



FAMILY III. ACHROMOBACTERACEAE BREED, 1945. 
(Achromobacteriaceae (sic) Breed, Jour. Bact., 50, 1945, 124.) 

A.chro.mo.bac.te.ra'ce.ae. M.L. mas.n. Achromohacler type genus of the family; -aceae 
ending to denote a family; M.L. fem.pl.n. Achromobacteraceae the Achromobacter family. 

Small to medium-sized rods which are usually uniform in shape. Motile by means of 
peritrichous flagella or non-motile. Gram-negative. May or may not liquefy gelatin. Growth 
on agar slants is non-chromogenic to yellow, orange, brown or even red; the pigment does 
not diffuse through the agar and apparently is carotenoid in nature. May produce acid but 
no gas from glucose and sometimes from other sugars; lactose is very rarely or never at- 
tacked. Certain species liquefy agar and/or attack alginates, others digest chitin. May or 
may not reduce nitrates. Litmus milk may be unchanged, slightly acid (not enough to be 
curdled) or alkaline. No luminescent species are known. Generally found as salt-water, 
fresh-water or soil forms, less commonly found as parasites or pathogens. Some plant path- 
ogens may belong here. 

Key to the genera of family Achromobacteraceae. 
I. Do not attack agar, alginates or chitin. Not active in the production of acid from sugars, 
especially lactose. 

A. Non-chromogenic on ordinary agar media, although the type species of Achroino- 
bacter produces yellow chromogenesis on potato. 

1. Litmus milk alkaline. No acid from carbohydrates. 

Genus I. Alcaligenes, p. 297. 

2. Litmus milk slightly acid (not enough to be curdled), unchanged or alkaline. 
Small amounts of acid are usually produced from hexoses. 

Genus II. Achromobacter, p. 300. 

B. Yellow, orange, brown or red chromogenesis produced on ordinary agar media; the 
pigment is non-water-soluble. 

Genus III. Flavobacterium, p. 309. 
II. Attack agar, alginates or chitin. Slightly more active in the fermentation of sugars than 
is the previous group, some even attacking lactose. Non-chromogenic or chromo- 
genic, usually with yellow or orange, always non-water-soluble pigments. 

A. Attack agar and/or alginates. 

Genus IV. Agarbacterium, p. 322. 

B. Attack chitin and sometimes horny substances. 

Genus V. Beneckea, p. 328. 



FAMILY III. ACHROMOBACTERACEAE 



297 



Genus I. Alcaligenes Castellani and Chahners, 1919* 
(Manual Trop. Med., 3rd ed., 1919, 936.) 

Al.ca.li'ge.nes. Arabic al the; Arabic noun gaily the ash of saltwort; French noun 
alcali alkali; English alkali; Gr. v. gennaio to produce; M.L. mas.n. Alcaligenes alkali-pro- 
ducing (bacteria). 

Rods which are either motile by means of peritrichous flagella or non-motile. Gram-neg- 
ative. May or may not liquefy gelatin and solidified blood serum. Litmus milk turned alka- 
line, with or without peptonization. Carbohydrates not utilized. Acetylmethylcarbinol 
not produced. Chromogenesis, when it occurs, is grayish yellow, brownish yellow or yellow. 
Generally found in the intestinal tracts of vertebrates or in dairy products. 

The type species is Alcaligenes faecalis Castellani and Chalmers. 



I. Gelatin not liquefied. 

A. Motile. 

B. Non-motile. 
1. Produces ropiness in milk. 



Key to the species of genus Alcaligenes. 

1 . A Icaligenes faecalis . 

2. Alcaligenes viscolactis. 



2. Found in the intestinal tract. 

3. Alcaligenes metalcaligenes . 
II. Gelatin liquefied. 

A. Motile. 

1. Milk peptonized; blood serum liquefied. 

4. Alcaligenes bookeri. 

2. Milk not peptonized; blood serum not liquefied. 

5. Alcaligenes recti. 

B. Non-motile. 

6. Alcaligenes marshallii. 



1. Alcaligenes faecalis Castellani and 
Chalmers, 1919. {Bacillus faecalis alcaligenes 
Petruschky, Cent. f. Bakt., I Abt., 19, 1896, 
187; Bacterium alcaligenes Mez,t Mikro- 
skopische Wasseranalyse, Berlin, 1898, 63; 
Castellani and Chalmers, Manual Trop. 
Med., 1919, 936.) 

fae.ca'lis. L. noun faex,faecis dregs; M.L. 
adj. faecalis fecal. 

Description from Petruschky (op. cit., 
1896, 187) as supplemented by Dr. Einar 
Leifson and Dr. Rudolph Hugh, Loyola 
University, Chicago, Illinois. 



Rods, 0.5 by 1.0 to 2.0 microns, occurring 
singly, in pairs and chains. Normally not 
encapsulated. Motile by means of peritri- 
chous flagella. Gram-negative. 

Gelatin colonies: Circular, grayish, trans- 
lucent. 

Gelatin stab: Gray surface growth. No 
liquefaction. 

Agar colonies: Opaque, entire, non-chro- 
mogenic. 

Agar slant: White, glistening, non-chro- 
mogenic. 



* Revised by Prof. H. J. Conn, New York State Experiment Station, Geneva, New York, 
June, 1938; further revision by Prof. Robert S. Breed, New York State Experiment Station, 
Geneva, New York, October, 1954. 

t While Mez (1898) proposed the binomial Bacterium alcaligenes earlier than Castellani 
and Chalmers (1919) proposed the binomial Alcaligenes faecalis,